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FDA Drug information

EC-NAPROXEN

Read time: 4 mins
Marketing start date: 28 Dec 2024

Summary of product characteristics


Adverse Reactions

6 ADVERSE REACTIONS The following adverse reactions are discussed in greater detail in other sections of the labeling: Cardiovascular Thrombotic Events [see Warnings and Precautions (5.1) ] GI Bleeding, Ulceration and Perforation [see Warnings and Precautions (5.2) ] Hepatotoxicity [see Warnings and Precautions (5.3) ] Hypertension [see Warnings and Precautions (5.4) ] Heart Failure and Edema [see Warnings and Precautions (5.5) ] Renal Toxicity and Hyperkalemia [see Warnings and Precautions (5.6) ] Anaphylactic Reactions [see Warnings and Precautions (5.7) ] Serious Skin Reactions [see Warnings and Precautions (5.9) ] Hematologic Toxicity [see Warnings and Precautions (5.11) ] Most common adverse reactions to naproxen were dyspepsia, abdominal pain, nausea, headache, rash, ecchymosis, and edema. (6.1) To report SUSPECTED ADVERSE REACTIONS, contact Woodward Pharma Services LLC at 1-888-514-4727 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Adverse reactions reported in controlled clinical trials in 960 patients treated for rheumatoid arthritis or osteoarthritis are listed below. In general, reactions in patients treated chronically were reported 2 to 10 times more frequently than they were in short-term studies in the 962 patients treated for mild to moderate pain or for dysmenorrhea. The most frequent complaints reported related to the gastrointestinal tract. A clinical study found gastrointestinal reactions to be more frequent and more severe in rheumatoid arthritis patients taking daily doses of 1500 mg naproxen compared to those taking 750 mg naproxen. In controlled clinical trials with about 80 pediatric patients and in well-monitored, open-label studies with about 400 pediatric patients with polyarticular juvenile idiopathic arthritis treated with naproxen, the incidence of rash and prolonged bleeding times were greater, the incidence of gastrointestinal and central nervous system reactions were about the same, and the incidence of other reactions were lower in pediatric patients than in adults. In patients taking naproxen in clinical trials, the most frequently reported adverse experiences in approximately 1% to 10% of patients were: Gastrointestinal (GI) Experiences, including: heartburn * , abdominal pain * , nausea * , constipation * , diarrhea, dyspepsia, stomatitis C entral Nervous System: headache * , dizziness * , drowsiness * , lightheadedness, vertigo Dermatologic: pruritus (itching) * , skin eruptions * , ecchymoses * , sweating, purpura Special Senses: tinnitus * , visual disturbances, hearing disturbances C ardiovascular: edema * , palpitations General: dyspnea * , thirst * Incidence of reported reaction between 3% and 9%. Those reactions occurring in less than 3% of the patients are unmarked. In patients taking NSAIDs, the following adverse experiences have also been reported in approximately 1% to 10% of patients. Gastrointestinal (GI) Experiences, including: flatulence, gross bleeding/perforation, GI ulcers (gastric/duodenal), vomiting General: abnormal renal function, anemia, elevated liver enzymes, increased bleeding time, rashes The following are additional adverse experiences reported in <1% of patients taking naproxen during clinical trials. Gastrointestinal: pancreatitis, vomiting Hepatobiliary: jaundice Hemic and Lymphatic: melena, thrombocytopenia, agranulocytosis Nervous System: inability to concentrate Dermatologic: skin rashes 6.2 Postmarketing Experience The following adverse reactions have been identified during post approval use of naproxen. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. The following are additional adverse experiences reported in <1% of patients taking naproxen during clinical trials and through postmarketing reports. Those adverse reactions observed through postmarketing reports are italicized. Body as a Whole: anaphylactoid reactions, angioneurotic edema, menstrual disorders, pyrexia (chills and fever) Cardiovascular: congestive heart failure, vasculitis, hypertension, pulmonary edema Gastrointestinal: inflammation, bleeding (sometimes fatal, particularly in the elderly), ulceration, perforation and obstruction of the upper or lower gastrointestinal tract. Esophagitis, stomatitis, hematemesis, colitis, exacerbation of inflammatory bowel disease (ulcerative colitis, Crohn’s disease). Hepatobiliary: abnormal liver function tests, hepatitis (some cases have been fatal) Hemic and Lymphatic: eosinophilia, leucopenia, granulocytopenia, hemolytic anemia, aplastic anemia Metabolic and Nutritional: hyperglycemia, hypoglycemia Nervous System: depression, dream abnormalities, insomnia, malaise, myalgia, muscle weakness, aseptic meningitis, cognitive dysfunction, convulsions Respiratory: eosinophilic pneumonitis, asthma Dermatologic: alopecia, urticaria, toxic epidermal necrolysis, erythema multiforme, erythema nodosum, fixed drug eruption, lichen planus, pustular reaction, systemic lupus erythematoses, bullous reactions, including Stevens-Johnson syndrome, photosensitive dermatitis, photosensitivity reactions, including rare cases resembling porphyria cutanea tarda (pseudoporphyria) or epidermolysis bullosa. If skin fragility, blistering or other symptoms suggestive of pseudoporphyria occur, treatment should be discontinued and the patient monitored. Special Senses: hearing impairment, corneal opacity, papillitis, retrobulbar optic neuritis, papilledema Urogenital: glomerular nephritis, hematuria, hyperkalemia, interstitial nephritis, nephrotic syndrome, renal disease, renal failure, renal papillary necrosis, raised serum creatinine Reproduction (female): infertility In patients taking NSAIDs, the following adverse experiences have also been reported in <1% of patients. Body as a Whole: fever, infection, sepsis, anaphylactic reactions, appetite changes, death Cardiovascular: hypertension, tachycardia, syncope, arrhythmia, hypotension, myocardial infarction Gastrointestinal: dry mouth, esophagitis, gastric/peptic ulcers, gastritis, glossitis, eructation Hepatobiliary: hepatitis, liver failure Hemic and Lymphatic: rectal bleeding, lymphadenopathy, pancytopenia Metabolic and Nutritional: weight changes Nervous System: anxiety, asthenia, confusion, nervousness, paresthesia, somnolence, tremors, convulsions, coma, hallucinations Respiratory: asthma, respiratory depression, pneumonia Dermatologic: exfoliative dermatitis Special Senses: blurred vision, conjunctivitis Urogenital: cystitis, dysuria, oliguria/polyuria, proteinuria

Contraindications

4 CONTRAINDICATIONS NAPROXEN Tablets, EC-NAPROXEN, and NAPROXEN SODIUM are contraindicated in the following patients: Known hypersensitivity (e.g., anaphylactic reactions and serious skin reactions) to naproxen or any components of the drug product [see Warnings and Precautions (5.7 , 5.9) ]. History of asthma, urticaria, or other allergic-type reactions after taking aspirin or other NSAIDs. Severe, sometimes fatal, anaphylactic reactions to NSAIDs have been reported in such patients [see Warnings and Precautions (5.7 , 5.8) ] . In the setting of coronary artery bypass graft (CABG) surgery [see Warnings and Precautions ( 5.1) ] . Known hypersensitivity to naproxen or any components of the drug product (4) History of asthma, urticaria, or other allergic-type reactions after taking aspirin or other NSAIDs (4) In the setting of CABG surgery (4)

Description

11 DESCRIPTION NAPROXEN (naproxen) tablets, EC-NAPROXEN (naproxen) delayed-release tablets and NAPROXEN SODIUM (naproxen sodium) tablets are nonsteroidal anti-inflammatory drugs available as follows: NAPROXEN tablets are available as yellow tablets containing 500 mg of naproxen for oral administration. EC-NAPROXEN delayed-release tablets are available as enteric-coated white tablets containing 375 mg of naproxen or 500 mg of naproxen for oral administration. NAPROXEN SODIUM tablets are available as dark blue tablets containing 550 mg of naproxen sodium for oral administration. Naproxen is a propionic acid derivative related to the arylacetic acid group of nonsteroidal anti-inflammatory drugs. The chemical names for naproxen and naproxen sodium are (S)-6-methoxy-α-methyl-2-naphthaleneacetic acid and (S)-6-methoxy-α-methyl-2-naphthaleneacetic acid, sodium salt, respectively. Naproxen has a molecular weight of 230.26 and a molecular formula of C 14 H 14 O 3 . Naproxen sodium has a molecular weight of 252.23 and a molecular formula of C 14 H 14 NaO 3 . Naproxen and naproxen sodium have the following structures, respectively: Naproxen is an odorless, white to off-white crystalline substance. It is lipid-soluble, practically insoluble in water at low pH and freely soluble in water at high pH. The octanol/water partition coefficient of naproxen at pH 7.4 is 1.6 to 1.8. Naproxen sodium is a white to creamy white, crystalline solid, freely soluble in water at neutral pH. The inactive ingredients in NAPROXEN tablets include: croscarmellose sodium, iron oxides, povidone and magnesium stearate. The inactive ingredients in EC-NAPROXEN delayed release tablets include: croscarmellose sodium, povidone and magnesium stearate. The enteric coating dispersion contains methacrylic acid copolymer, talc, triethyl citrate, sodium hydroxide and purified water. The imprinting on the tablets is black ink. The dissolution of this enteric-coated naproxen tablet is pH dependent with rapid dissolution above pH 6. There is no dissolution below pH 4. The inactive ingredients in NAPROXEN SODIUM tablets include: magnesium stearate, microcrystalline cellulose, povidone and talc. The coating suspension may contain hydroxypropyl methylcellulose 2910, Opaspray K-1-4227, polyethylene glycol 8000 or Opadry YS-1-4216. Structural Formula

Dosage And Administration

2 DOSAGE AND ADMINISTRATION Use the lowest effective dosage for shortest duration consistent with individual patient treatment goals. (2.1) Rheumatoid Arthritis, Osteoarthritis, and Ankylosing Spondylitis NAPROXEN Tablets 250 mg (one-half tablet) 500 mg twice daily NAPROXEN SODIUM 275 mg (one-half tablet) 550 mg twice daily EC-NAPROXEN 375 mg or 500 mg twice daily To maintain the integrity of the enteric coating, the EC-NAPROXEN tablet should not be broken, crushed or chewed during ingestion. The dose may be adjusted up or down depending on the clinical response of the patient. In patients who tolerate lower doses well, the dose may be increased to naproxen 1,500 mg/day for up to 6 months. Polyarticular Juvenile Idiopathic Arthritis NAPROXEN Tablets may not allow for the flexible dose titration needed in pediatric patients with polyarticular juvenile idiopathic arthritis. A liquid formulation may be more appropriate. Recommended total daily dose of naproxen is approximately 10 mg/kg given in 2 divided doses. Dosing with NAPROXEN Tablets is not appropriate for children weighing less than 50 kilograms. Management of Pain, Primary Dysmenorrhea, and Acute Tendonitis and Bursitis Recommended starting dose 550 mg of naproxen sodium as NAPROXEN SODIUM followed by 550 mg every 12 hours or 275 mg every 6 to 8 hours as required. The initial total daily dose should not exceed 1375 mg of naproxen sodium. Thereafter, the total daily dose should not exceed 1100 mg of naproxen sodium. NAPROXEN SODIUM is recommended for the management of acute painful conditions when prompt onset of pain relief is desired. Acute Gout Recommended starting dose 750 mg of NAPROXEN Tablets followed by 250 mg every 8 hours until the attack has subsided. NAPROXEN SODIUM may also be used at a starting dose of 825 mg followed by 275 mg every 8 hours. EC-NAPROXEN is not recommended because of the delay in absorption. 2.1 General Dosing Instructions Carefully consider the potential benefits and risks of NAPROXEN Tablets, EC-NAPROXEN and NAPROXEN SODIUM and other treatment options before deciding to use NAPROXEN Tablets, EC-NAPROXEN and NAPROXEN SODIUM. Use the lowest effective dose for the shortest duration consistent with individual patient treatment goals [see Warnings and Precautions (5) ] . After observing the response to initial therapy with NAPROXEN Tablets, EC-NAPROXEN or NAPROXEN SODIUM, the dose and frequency should be adjusted to suit an individual patient’s needs. To maintain the integrity of the enteric coating, the EC-NAPROXEN tablet should not be broken, crushed or chewed during ingestion. Naproxen-containing products such as NAPROXEN, EC-NAPROXEN and NAPROXEN SODIUM, and other naproxen products should not be used concomitantly since they all circulate in the plasma as the naproxen anion. 2.2 Rheumatoid Arthritis, Osteoarthritis and Ankylosing Spondylitis The recommended dosages of NAPROXEN Tablets, NAPROXEN SODIUM, and EC-NAPROXEN are shown in Table 1. Table 1: Recommended dosages for NAPROXEN Tablets, NAPROXEN SODIUM, and EC-NAPROXEN NAPROXEN Tablets 250 mg (one-half tablet) 500 mg twice daily NAPROXEN SODIUM 275 mg (one-half tablet) 550 mg (naproxen 500 mg with 50 mg sodium) twice daily EC-NAPROXEN 375 mg or 500 mg twice daily During long-term administration, the dose of naproxen may be adjusted up or down depending on the clinical response of the patient. A lower daily dose may suffice for long-term administration. The morning and evening doses do not have to be equal in size and the administration of the drug more frequently than twice daily is not necessary. The morning and evening doses do not have to be equal in size and administration of the drug more frequently than twice daily does not generally make a difference in response. In patients who tolerate lower doses well, the dose may be increased to naproxen 1500 mg/day for limited periods of up to 6 months when a higher level of anti-inflammatory/analgesic activity is required. When treating such patients with naproxen 1500 mg/day, the physician should observe sufficient increased clinical benefits to offset the potential increased risk. 2.3 Polyarticular Juvenile Idiopathic Arthritis Naproxen solid-oral dosage forms may not allow for the flexible dose titration needed in pediatric patients with polyarticular juvenile idiopathic arthritis. A liquid formulation may be more appropriate for weight-based dosing and due to the need for dose flexibility in children. In pediatric patients, doses of 5 mg/kg/day produced plasma levels of naproxen similar to those seen in adults taking 500 mg of naproxen [see Clinical Pharmacology (12) ] . The recommended total daily dose of naproxen is approximately 10 mg/kg given in 2 divided doses. Dosing with NAPROXEN tablets is not appropriate for children weighing less than 50 kilograms. 2.4 Management of Pain, Primary Dysmenorrhea, and Acute Tendonitis and Bursitis The recommended starting dose of NAPROXEN SODIUM (naproxen sodium) tablets is 550 mg followed by 550 mg every 12 hours or 275 mg (one half of a 550 mg tablet) every 6 to 8 hours as required. The initial total daily dose should not exceed 1375 mg (two and one-half tablets) of naproxen sodium. Thereafter, the total daily dose should not exceed 1100 mg of naproxen sodium. Because the sodium salt of naproxen is more rapidly absorbed, NAPROXEN SODIUM is recommended for the management of acute painful conditions when prompt onset of pain relief is desired. NAPROXEN Tablets may also be used. The recommended starting dose of NAPROXEN Tablets is 500 mg followed by 250 mg (one half of a 500 mg NAPROXEN tablet) every 6-8 hours as required.. The total daily dose should not exceed 1250 mg of naproxen. EC-NAPROXEN is not recommended for initial treatment of acute pain because absorption of naproxen is delayed compared to other naproxen-containing products [see Clinical Pharmacology (12) ] . 2.5 Acute Gout The recommended starting dose is 750 mg (one and one-half tablets) of NAPROXEN Tablets followed by 250 mg (one-half tablet) every 8 hours until the attack has subsided. NAPROXEN SODIUM may also be used at a starting dose of 825 mg (one and one-half tablets) followed by 275 mg (one-half tablet) every 8 hours. EC-NAPROXEN is not recommended because of the delay in absorption. 2.6 Non-Interchangeability with Other Formulations of Naproxen Different dose strengths and formulations (e.g., tablets, suspension) of naproxen are not interchangeable. This difference should be taken into consideration when changing strengths or formulations.

Indications And Usage

1 INDICATIONS AND USAGE NAPROXEN Tablets, EC-NAPROXEN, and NAPROXEN SODIUM are indicated for: the relief of the signs and symptoms of: rheumatoid arthritis osteoarthritis ankylosing spondylitis polyarticular juvenile idiopathic arthritis NAPROXEN Tablets and NAPROXEN SODIUM are also indicated for: the relief of signs and symptoms of: tendonitis bursitis acute gout the management of: pain primary dysmenorrhea NAPROXEN Tablets, EC-NAPROXEN, and NAPROXEN SODIUM are non-steroidal anti-inflammatory drugs indicated for: the relief of the signs and symptoms of: rheumatoid arthritis osteoarthritis ankylosing spondylitis polyarticular juvenile idiopathic arthritis NAPROXEN Tablets and NAPROXEN SODIUM are also indicated for: the relief of signs and symptoms of: tendonitis bursitis acute gout the management of: pain primary dysmenorrhea

Overdosage

10 OVERDOSAGE Symptoms following acute NSAID overdosages have been typically limited to lethargy, drowsiness, nausea, vomiting, and epigastric pain, which have been generally reversible with supportive care. Gastrointestinal bleeding has occurred. Hypertension, acute renal failure, respiratory depression, and coma have occurred, but were rare [ see Warnings and Precautions ( 5.1 , 5.2 ) ]. Because naproxen sodium may be rapidly absorbed, high and early blood levels should be anticipated. A few patients have experienced convulsions, but it is not clear whether or not these were drug-related. It is not known what dose of the drug would be life threatening. [see Warnings and Precautions ( 5.1 , 5.2 , 5.4 , 5.6) ]. Manage patients with symptomatic and supportive care following an NSAID overdosage. There are no specific antidotes. Consider emesis and/or activated charcoal (60 grams to 100 grams in adults, 1 gram to 2 grams per kg of body weight in pediatric patients) and/or osmotic cathartic in symptomatic patients seen within four hours of ingestion or in patients with a large overdosage (5 to 10 times the recommended dosage). Forced diuresis, alkalinization of urine, hemodialysis, or hemoperfusion may not be useful due to high protein binding. For additional information about overdosage treatment contact a poison control center (1-800-222-1222).

Drug Interactions

7 DRUG INTERACTIONS See Table 1 for clinically significant drug interactions with naproxen. Table 1: Clinically Significant Drug Interactions with naproxen Drugs That Interfere with Hemostasis Clinical Impact: Naproxen and anticoagulants such as warfarin have a synergistic effect on bleeding. The concomitant use of naproxen and anticoagulants have an increased risk of serious bleeding compared to the use of either drug alone. Serotonin release by platelets plays an important role in hemostasis. Case-control and cohort epidemiological studies showed that concomitant use of drugs that interfere with serotonin reuptake and an NSAID may potentiate the risk of bleeding more than an NSAID alone. Intervention: Monitor patients with concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM with anticoagulants (e.g., warfarin), antiplatelet agents (e.g., aspirin), selective serotonin reuptake inhibitors (SSRIs), and serotonin norepinephrine reuptake inhibitors (SNRIs) for signs of bleeding [see Warnings and Precautions (5.11) ] . Aspirin Clinical Impact: A pharmacodynamic (PD) study has demonstrated an interaction in which lower dose naproxen (220mg/day or 220mg twice daily) interfered with the antiplatelet effect of low-dose immediate-release aspirin, with the interaction most marked during the washout period of naproxen [ see Clinical Pharmacology (12.2) ]. There is reason to expect that the interaction would be present with prescription doses of naproxen or with enteric-coated low-dose aspirin; however, the peak interference with aspirin function may be later than observed in the PD study due to the longer washout period. Controlled clinical studies showed that the concomitant use of NSAIDs and analgesic doses of aspirin does not produce any greater therapeutic effect than the use of NSAIDs alone. In a clinical study, the concomitant use of an NSAID and aspirin was associated with a significantly increased incidence of GI adverse reactions as compared to use of the NSAID alone [see Warnings and Precautions (5.2) ] . Intervention: Because there may be an increased risk of cardiovascular events following discontinuation of naproxen due to the interference with the antiplatelet effect of aspirin during the washout period, for patients taking low-dose aspirin for cardioprotection who require intermittent analgesics, consider use of an NSAID that does not interfere with the antiplatelet effect of aspirin, or non-NSAID analgesics where appropriate. Concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and analgesic doses of aspirin is not generally recommended because of the increased risk of bleeding [see Warnings and Precautions ( 5.11) ]. NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM are not substitute for low dose aspirin for cardiovascular protection. ACE Inhibitors, Angiotensin Receptor Blockers, and Beta-Blockers Clinical Impact: NSAIDs may diminish the antihypertensive effect of angiotensin converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), or beta-blockers (including propranolol). In patients who are elderly, volume-depleted (including those on diuretic therapy), or have renal impairment, co-administration of an NSAID with ACE inhibitors or ARBs may result in deterioration of renal function, including possible acute renal failure. These effects are usually reversible. Intervention: During concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and ACE-inhibitors, ARBs, or beta-blockers, monitor blood pressure to ensure that the desired blood pressure is obtained. During concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and ACE-inhibitors or ARBs in patients who are elderly, volume-depleted, or have impaired renal function, monitor for signs of worsening renal function [ see Warnings and Precautions (5.6) ]. When these drugs are administered concomitantly, patients should be adequately hydrated. Assess renal function at the beginning of the concomitant treatment and periodically thereafter. Diuretics Clinical Impact: Clinical studies, as well as post-marketing observations, showed that NSAIDs reduced the natriuretic effect of loop diuretics (e.g., furosemide) and thiazide diuretics in some patients. This effect has been attributed to the NSAID inhibition of renal prostaglandin synthesis. Intervention During concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM with diuretics, observe patients for signs of worsening renal function, in addition to assuring diuretic efficacy including antihypertensive effects [ see Warnings and Precautions (5.6) ]. Digoxin Clinical Impact: The concomitant use of naproxen with digoxin has been reported to increase the serum concentration and prolong the half-life of digoxin. Intervention: During concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and digoxin, monitor serum digoxin levels. Lithium Clinical Impact: NSAIDs have produced elevations in plasma lithium levels and reductions in renal lithium clearance. The mean minimum lithium concentration increased 15%, and the renal clearance decreased by approximately 20%. This effect has been attributed to NSAID inhibition of renal prostaglandin synthesis. Intervention: During concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and lithium, monitor patients for signs of lithium toxicity. Methotrexate Clinical Impact: Concomitant use of NSAIDs and methotrexate may increase the risk for methotrexate toxicity (e.g., neutropenia, thrombocytopenia, renal dysfunction). Intervention: During concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and methotrexate, monitor patients for methotrexate toxicity. Cyclosporine Clinical Impact: Concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and cyclosporine may increase cyclosporine’s nephrotoxicity. Intervention: During concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and cyclosporine, monitor patients for signs of worsening renal function. NSAIDs and Salicylates Clinical Impact: Concomitant use of naproxen with other NSAIDs or salicylates (e.g., diflunisal, salsalate) increases the risk of GI toxicity, with little or no increase in efficacy [ see Warnings and Precautions (5.2) ]. Intervention: The concomitant use of naproxen with other NSAIDs or salicylates is not recommended. Pemetrexed Clinical Impact: Concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and pemetrexed may increase the risk of pemetrexed-associated myelosuppression, renal, and GI toxicity (see the pemetrexed prescribing information). Intervention: During concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and pemetrexed, in patients with renal impairment whose creatinine clearance ranges from 45 to 79 mL/min, monitor for myelosuppression, renal and GI toxicity. NSAIDs with short elimination half-lives (e.g., diclofenac, indomethacin) should be avoided for a period of two days before, the day of, and two days following administration of pemetrexed. In the absence of data regarding potential interaction between pemetrexed and NSAIDs with longer half-lives (e.g., meloxicam, nabumetone), patients taking these NSAIDs should interrupt dosing for at least five days before, the day of, and two days following pemetrexed administration. Antacids and Sucralfate Clinical Impact: Concomitant administration of some antacids (magnesium oxide or aluminum hydroxide) and sucralfate can delay the absorption of naproxen. Intervention: Concomitant administration of antacids such as magnesium oxide or aluminum hydroxide, and sucralfate with NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM is not recommended. Cholestyramine Clinical Impact: Concomitant administration of cholestyramine can delay the absorption of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM. Intervention: Concomitant administration of cholestyramine with naproxen tablets is not recommended. Probenecid Clinical Impact: Probenecid given concurrently increases naproxen anion plasma levels and extends its plasma half-life significantly. Intervention: Patients simultaneously receiving NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and probenecid should be observed for adjustment of dose if required. Other albumin-bound drugs Clinical Impact: Naproxen is highly bound to plasma albumin; it thus has a theoretical potential for interaction with other albumin-bound drugs such as coumarin-type anticoagulants, sulphonylureas, hydantoins, other NSAIDs, and aspirin. Intervention: Patients simultaneously receiving NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and a hydantoin, sulphonamide or sulphonylurea should be observed for adjustment of dose if required. Drug/Laboratory Test Interactions Bleeding times Clinical Impact: Naproxen may decrease platelet aggregation and prolong bleeding time. Intervention: This effect should be kept in mind when bleeding times are determined. Porter-Silber test Clinical Impact: The administration of naproxen may result in increased urinary values for 17ketogenic steroids because of an interaction between the drug and/or its metabolites with m-di-nitrobenzene used in this assay. Intervention: Although 17-hydroxy-corticosteroid measurements (Porter-Silber test) do not appear to be artifactually altered, it is suggested that therapy with naproxen be temporarily discontinued 72 hours before adrenal function tests are performed if the Porter-Silber test is to be used. Urinary assays of 5-hydroxy indoleacetic acid (5HIAA) Clinical Impact: Naproxen may interfere with some urinary assays of 5-hydroxy indoleacetic acid (5HIAA). Intervention: This effect should be kept in mind when urinary 5-hydroxy indoleacetic acid is determined. Drugs that Interfere with Hemostasis (e.g. warfarin, aspirin, SSRIs/SNRIs): Monitor patients for bleeding who are concomitantly taking NAPROXEN Tablets, EC-NAPROXEN or NAPROXEN SODIUM with drugs that interfere with hemostasis. Concomitant use of NAPROXEN Tablets, EC-NAPROXEN or NAPROXEN SODIUM and analgesic doses of aspirin is not generally recommended. (7) ACE inhibitors, Angiotensin Receptor Blockers (ARB), or Beta-Blockers: Concomitant use with NAPROXEN Tablets, EC-NAPROXEN or NAPROXEN SODIUM may diminish the antihypertensive effect of these drugs. Monitor blood pressure. (7) ACE Inhibitors and ARBs: Concomitant use with NAPROXEN Tablets, EC-NAPROXEN or NAPROXEN SODIUM in elderly, volume depleted, or those with renal impairment may result in deterioration of renal function. In such high risk patients, monitor for signs of worsening renal function. (7) Diuretics: NSAIDs can reduce natriuretic effect of furosemide and thiazide diuretics. Monitor patients to assure diuretic efficacy including antihypertensive effects. (7) Digoxin: Concomitant use with NAPROXEN Tablets, EC-NAPROXEN or NAPROXEN SODIUM can increase serum concentration and prolong half-life of digoxin. Monitor serum digoxin levels. (7)

Drug Interactions Table

Drugs That Interfere with Hemostasis

Clinical Impact:

  • Naproxen and anticoagulants such as warfarin have a synergistic effect on bleeding. The concomitant use of naproxen and anticoagulants have an increased risk of serious bleeding compared to the use of either drug alone.
  • Serotonin release by platelets plays an important role in hemostasis. Case-control and cohort epidemiological studies showed that concomitant use of drugs that interfere with serotonin reuptake and an NSAID may potentiate the risk of bleeding more than an NSAID alone.
  • Intervention:

  • Monitor patients with concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM with anticoagulants (e.g., warfarin), antiplatelet agents (e.g., aspirin), selective serotonin reuptake inhibitors (SSRIs), and serotonin norepinephrine reuptake inhibitors (SNRIs) for signs of bleeding [see Warnings and Precautions (5.11)].
  • Aspirin

    Clinical Impact:

    A pharmacodynamic (PD) study has demonstrated an interaction in which lower dose naproxen (220mg/day or 220mg twice daily) interfered with the antiplatelet effect of low-dose immediate-release aspirin, with the interaction most marked during the washout period of naproxen [see Clinical Pharmacology (12.2)]. There is reason to expect that the interaction would be present with prescription doses of naproxen or with enteric-coated low-dose aspirin; however, the peak interference with aspirin function may be later than observed in the PD study due to the longer washout period. Controlled clinical studies showed that the concomitant use of NSAIDs and analgesic doses of aspirin does not produce any greater therapeutic effect than the use of NSAIDs alone. In a clinical study, the concomitant use of an NSAID and aspirin was associated with a significantly increased incidence of GI adverse reactions as compared to use of the NSAID alone [see Warnings and Precautions (5.2)].

    Intervention:

    Because there may be an increased risk of cardiovascular events following discontinuation of naproxen due to the interference with the antiplatelet effect of aspirin during the washout period, for patients taking low-dose aspirin for cardioprotection who require intermittent analgesics, consider use of an NSAID that does not interfere with the antiplatelet effect of aspirin, or non-NSAID analgesics where appropriate. Concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and analgesic doses of aspirin is not generally recommended because of the increased risk of bleeding [see Warnings and Precautions (5.11)].

    NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM are not substitute for low dose aspirin for cardiovascular protection.

    ACE Inhibitors, Angiotensin Receptor Blockers, and Beta-Blockers

    Clinical Impact:

  • NSAIDs may diminish the antihypertensive effect of angiotensin converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), or beta-blockers (including propranolol).
  • In patients who are elderly, volume-depleted (including those on diuretic therapy), or have renal impairment, co-administration of an NSAID with ACE inhibitors or ARBs may result in deterioration of renal function, including possible acute renal failure. These effects are usually reversible.
  • Intervention:

  • During concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and ACE-inhibitors, ARBs, or beta-blockers, monitor blood pressure to ensure that the desired blood pressure is obtained.
  • During concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and ACE-inhibitors or ARBs in patients who are elderly, volume-depleted, or have impaired renal function, monitor for signs of worsening renal function [see Warnings and Precautions (5.6)].
  • When these drugs are administered concomitantly, patients should be adequately hydrated. Assess renal function at the beginning of the concomitant treatment and periodically thereafter.
  • Diuretics

    Clinical Impact:

    Clinical studies, as well as post-marketing observations, showed that NSAIDs reduced the natriuretic effect of loop diuretics (e.g., furosemide) and thiazide diuretics in some patients. This effect has been attributed to the NSAID inhibition of renal prostaglandin synthesis.

    Intervention

    During concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM with diuretics, observe patients for signs of worsening renal function, in addition to assuring diuretic efficacy including antihypertensive effects [see Warnings and Precautions (5.6)].

    Digoxin

    Clinical Impact:

    The concomitant use of naproxen with digoxin has been reported to increase the serum concentration and prolong the half-life of digoxin.

    Intervention:

    During concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and digoxin, monitor serum digoxin levels.

    Lithium

    Clinical Impact:

    NSAIDs have produced elevations in plasma lithium levels and reductions in renal lithium clearance. The mean minimum lithium concentration increased 15%, and the renal clearance decreased by approximately 20%. This effect has been attributed to NSAID inhibition of renal prostaglandin synthesis.

    Intervention:

    During concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and lithium, monitor patients for signs of lithium toxicity.

    Methotrexate

    Clinical Impact:

    Concomitant use of NSAIDs and methotrexate may increase the risk for methotrexate toxicity (e.g., neutropenia, thrombocytopenia, renal dysfunction).

    Intervention:

    During concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and methotrexate, monitor patients for methotrexate toxicity.

    Cyclosporine

    Clinical Impact:

    Concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and cyclosporine may increase cyclosporine’s nephrotoxicity.

    Intervention:

    During concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and cyclosporine, monitor patients for signs of worsening renal function.

    NSAIDs and Salicylates

    Clinical Impact:

    Concomitant use of naproxen with other NSAIDs or salicylates (e.g., diflunisal, salsalate) increases the risk of GI toxicity, with little or no increase in efficacy [see Warnings and Precautions (5.2)].

    Intervention:

    The concomitant use of naproxen with other NSAIDs or salicylates is not recommended.

    Pemetrexed

    Clinical Impact:

    Concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and pemetrexed may increase the risk of pemetrexed-associated myelosuppression, renal, and GI toxicity (see the pemetrexed prescribing information).

    Intervention:

    During concomitant use of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and pemetrexed, in patients with renal impairment whose creatinine clearance ranges from 45 to 79 mL/min, monitor for myelosuppression, renal and GI toxicity.

    NSAIDs with short elimination half-lives (e.g., diclofenac, indomethacin) should be avoided for a period of two days before, the day of, and two days following administration of pemetrexed.

    In the absence of data regarding potential interaction between pemetrexed and NSAIDs with longer half-lives (e.g., meloxicam, nabumetone), patients taking these NSAIDs should interrupt dosing for at least five days before, the day of, and two days following pemetrexed administration.

    Antacids and Sucralfate

    Clinical Impact:

    Concomitant administration of some antacids (magnesium oxide or aluminum hydroxide) and sucralfate can delay the absorption of naproxen.

    Intervention:

    Concomitant administration of antacids such as magnesium oxide or aluminum hydroxide, and sucralfate with NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM is not recommended.

    Cholestyramine

    Clinical Impact:

    Concomitant administration of cholestyramine can delay the absorption of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM.

    Intervention:

    Concomitant administration of cholestyramine with naproxen tablets is not recommended.

    Probenecid

    Clinical Impact:

    Probenecid given concurrently increases naproxen anion plasma levels and extends its plasma half-life significantly.

    Intervention:

    Patients simultaneously receiving NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and probenecid should be observed for adjustment of dose if required.

    Other albumin-bound drugs

    Clinical Impact:

    Naproxen is highly bound to plasma albumin; it thus has a theoretical potential for interaction with other albumin-bound drugs such as coumarin-type anticoagulants, sulphonylureas, hydantoins, other NSAIDs, and aspirin.

    Intervention:

    Patients simultaneously receiving NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and a hydantoin, sulphonamide or sulphonylurea should be observed for adjustment of dose if required.

    Clinical Pharmacology

    12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Naproxen has analgesic, anti-inflammatory, and antipyretic properties. NAPROXEN SODIUM (naproxen sodium) has been developed as a more rapidly absorbed formulation of naproxen for use as an analgesic. The mechanism of action of naproxen, like that of other NSAIDs, is not completely understood but involves inhibition of cyclooxygenase (COX-1 and COX-2). Naproxen is a potent inhibitor of prostaglandin synthesis in vitro . Naproxen concentrations reached during therapy have produced in vivo effects. Prostaglandins sensitize afferent nerves and potentiate the action of bradykinin in inducing pain in animal models. Prostaglandins are mediators of inflammation. Because naproxen is an inhibitor of prostaglandin synthesis, its mode of action may be due to a decrease of prostaglandins in peripheral tissues. 12.2 Pharmacodynamics In a healthy volunteer study, 10 days of concomitant administration of naproxen 220 mg once-daily with low-dose immediate-release aspirin (81 mg) showed an interaction with the antiplatelet activity of aspirin as measured by % serum thromboxane B2 inhibition at 24 hours following the day 10 dose [98.7% (aspirin alone) vs 93.1% (naproxen and aspirin)]. The interaction was observed even following discontinuation of naproxen on day 11 (while aspirin dose was continued) but normalized by day 13. In the same study, the interaction was greater when naproxen was administered 30 minutes prior to aspirin [98.7% vs 87.7%] and minimal when aspirin was administered 30 minutes prior to naproxen [98.7% vs 95.4%]. Following administration of naproxen 220 mg twice-daily with low-dose immediate-release aspirin (first naproxen dose given 30 minutes prior to aspirin), the interaction was minimal at 24 h following day 10 dose [98.7% vs 95.7%]. However, the interaction was more prominent after discontinuation of naproxen (washout) on day 11 [98.7% vs 84.3%] and did not normalize completely by day 13 [98.5% vs 90.7%]. [see Drug Interactions (7) ] . 12.3 Pharmacokinetics Naproxen and naproxen sodium is rapidly and completely absorbed from the gastrointestinal tract with an in vivo bioavailability of 95%. The different dosage forms of NAPROXEN are bioequivalent in terms of extent of absorption (AUC) and peak concentration (C max ); however, the products do differ in their pattern of absorption. These differences between naproxen products are related to both the chemical form of naproxen used and its formulation. Even with the observed differences in pattern of absorption, the elimination half-life of naproxen is unchanged across products ranging from 12 to 17 hours. Steady-state levels of naproxen are reached in 4 days to 5 days, and the degree of naproxen accumulation is consistent with this half-life. This suggests that the differences in pattern of release play only a negligible role in the attainment of steady-state plasma levels. Absorption NAPROXEN Tablets/NAPROXEN SODIUM: After administration of NAPROXEN Tablets, peak plasma levels are attained in 2 to 4 hours. After oral administration of NAPROXEN SODIUM, peak plasma levels are attained in 1 to 2 hours. The difference in rates between the two products is due to the increased aqueous solubility of the sodium salt of naproxen used in NAPROXEN SODIUM. EC-NAPROXEN: EC-NAPROXEN is designed with a pH-sensitive coating to provide a barrier to disintegration in the acidic environment of the stomach and to lose integrity in the more neutral environment of the small intestine. The enteric polymer coating selected for EC-NAPROXEN dissolves above pH 6. When EC-NAPROXEN was given to fasted subjects, peak plasma levels were attained about 4 to 6 hours following the first dose (range: 2 to 12 hours). An in vivo study in man using radiolabeled EC-NAPROXEN tablets demonstrated that EC-NAPROXEN dissolves primarily in the small intestine rather than in the stomach, so the absorption of the drug is delayed until the stomach is emptied. When EC-NAPROXEN and NAPROXEN were given to fasted subjects (n=24) in a crossover study following 1 week of dosing, differences in time to peak plasma levels (T max ) were observed, but there were no differences in total absorption as measured by C max and AUC: EC-NAPROXEN* 500 mg bid EC-NAPROXEN* 500 mg bid C max (µg/mL) 94.9 (18%) 97.4 (13%) T max (hours) 4 (39%) 1.9 (61%) AUC 0–12 hr (µg·hr/mL) 845 (20%) 767 (15%) *Mean value (coefficient of variation) Antacid Effects When EC-NAPROXEN was given as a single dose with antacid (54 mEq buffering capacity), the peak plasma levels of naproxen were unchanged, but the time to peak was reduced (mean T max fasted 5.6 hours, mean T max with antacid 5 hours), although not significantly. [ see Drug Interactions (7) ]. Food Effects When EC-NAPROXEN was given as a single dose with food, peak plasma levels in most subjects were achieved in about 12 hours (range: 4 to 24 hours). Residence time in the small intestine until disintegration was independent of food intake. The presence of food prolonged the time the tablets remained in the stomach, time to first detectable serum naproxen levels, and time to maximal naproxen levels (T max ), but did not affect peak naproxen levels (C max ). Distribution Naproxen has a volume of distribution of 0.16 L/kg. At therapeutic levels naproxen is greater than 99% albumin-bound. At doses of naproxen greater than 500 mg/day there is less than proportional increase in plasma levels due to an increase in clearance caused by saturation of plasma protein binding at higher doses (average trough C ss 36.5, 49.2 and 56.4 mg/L with 500, 1,000 and 1,500 mg daily doses of naproxen, respectively). The naproxen anion has been found in the milk of lactating women at a concentration equivalent to approximately 1% of maximum naproxen concentration in plasma [see Use in Specific Populations ( 8.2 ) ] . Elimination Metabolism Naproxen is extensively metabolized in the liver to 6-0-desmethyl naproxen, and both parent and metabolites do not induce metabolizing enzymes. Both naproxen and 6-0-desmethyl naproxen are further metabolized to their respective acylglucuronide conjugated metabolites. Excretion The clearance of naproxen is 0.13 mL/min/kg. Approximately 95% of the naproxen from any dose is excreted in the urine, primarily as naproxen (<1%), 6-0-desmethyl naproxen (<1%) or their conjugates (66% to 92%). The plasma half-life of the naproxen anion in humans ranges from 12 to 17 hours. The corresponding half-lives of both naproxen’s metabolites and conjugates are shorter than 12 hours, and their rates of excretion have been found to coincide closely with the rate of naproxen clearance from the plasma. Small amounts, 3% or less of the administered dose, are excreted in the feces. In patients with renal failure metabolites may accumulate [ see Warnings and Precautions (5.6) ]. Specific Populations Pediatric: In pediatric patients aged 5 to 16 years with arthritis, plasma naproxen levels following a 5 mg/kg single dose of naproxen suspension [ see Dosage and Administration (2) ] were found to be similar to those found in normal adults following a 500 mg dose. The terminal half-life appears to be similar in pediatric and adult patients. Pharmacokinetic studies of naproxen were not performed in pediatric patients younger than 5 years of age. Pharmacokinetic parameters appear to be similar following administration of naproxen suspension or tablets in pediatric patients. Geriatric: Studies indicate that although total plasma concentration of naproxen is unchanged, the unbound plasma fraction of naproxen is increased in the elderly, although the unbound fraction is <1% of the total naproxen concentration. Unbound trough naproxen concentrations in elderly subjects have been reported to range from 0.12% to 0.19% of total naproxen concentration, compared with 0.05% to 0.075% in younger subjects. Hepatic Impairment: Naproxen pharmacokinetics have not been determined in subjects with hepatic insufficiency. Chronic alcoholic liver disease and probably other diseases with decreased or abnormal plasma proteins (albumin) reduce the total plasma concentration of naproxen, but the plasma concentration of unbound naproxen is increased. Renal Impairment: Naproxen pharmacokinetics have not been determined in subjects with renal insufficiency. Given that naproxen, its metabolites and conjugates are primarily excreted by the kidney, the potential exists for naproxen metabolites to accumulate in the presence of renal insufficiency. Elimination of naproxen is decreased in patients with severe renal impairment. Drug Interaction Studies Aspirin: When NSAIDs were administered with aspirin, the protein binding of NSAIDs were reduced, although the clearance of free NSAID was not altered. The clinical significance of this interaction is not known. See Table 1 for clinically significant drug interactions of NSAIDs with aspirin [see Drug Interactions (7) ].

    Clinical Pharmacology Table

    EC-NAPROXEN* 500 mg bidEC-NAPROXEN* 500 mg bid
    Cmax (µg/mL)94.9 (18%)97.4 (13%)
    Tmax (hours)4 (39%)1.9 (61%)
    AUC0–12 hr (µg·hr/mL)845 (20%)767 (15%)

    Mechanism Of Action

    12.1 Mechanism of Action Naproxen has analgesic, anti-inflammatory, and antipyretic properties. NAPROXEN SODIUM (naproxen sodium) has been developed as a more rapidly absorbed formulation of naproxen for use as an analgesic. The mechanism of action of naproxen, like that of other NSAIDs, is not completely understood but involves inhibition of cyclooxygenase (COX-1 and COX-2). Naproxen is a potent inhibitor of prostaglandin synthesis in vitro . Naproxen concentrations reached during therapy have produced in vivo effects. Prostaglandins sensitize afferent nerves and potentiate the action of bradykinin in inducing pain in animal models. Prostaglandins are mediators of inflammation. Because naproxen is an inhibitor of prostaglandin synthesis, its mode of action may be due to a decrease of prostaglandins in peripheral tissues.

    Pharmacokinetics

    12.3 Pharmacokinetics Naproxen and naproxen sodium is rapidly and completely absorbed from the gastrointestinal tract with an in vivo bioavailability of 95%. The different dosage forms of NAPROXEN are bioequivalent in terms of extent of absorption (AUC) and peak concentration (C max ); however, the products do differ in their pattern of absorption. These differences between naproxen products are related to both the chemical form of naproxen used and its formulation. Even with the observed differences in pattern of absorption, the elimination half-life of naproxen is unchanged across products ranging from 12 to 17 hours. Steady-state levels of naproxen are reached in 4 days to 5 days, and the degree of naproxen accumulation is consistent with this half-life. This suggests that the differences in pattern of release play only a negligible role in the attainment of steady-state plasma levels. Absorption NAPROXEN Tablets/NAPROXEN SODIUM: After administration of NAPROXEN Tablets, peak plasma levels are attained in 2 to 4 hours. After oral administration of NAPROXEN SODIUM, peak plasma levels are attained in 1 to 2 hours. The difference in rates between the two products is due to the increased aqueous solubility of the sodium salt of naproxen used in NAPROXEN SODIUM. EC-NAPROXEN: EC-NAPROXEN is designed with a pH-sensitive coating to provide a barrier to disintegration in the acidic environment of the stomach and to lose integrity in the more neutral environment of the small intestine. The enteric polymer coating selected for EC-NAPROXEN dissolves above pH 6. When EC-NAPROXEN was given to fasted subjects, peak plasma levels were attained about 4 to 6 hours following the first dose (range: 2 to 12 hours). An in vivo study in man using radiolabeled EC-NAPROXEN tablets demonstrated that EC-NAPROXEN dissolves primarily in the small intestine rather than in the stomach, so the absorption of the drug is delayed until the stomach is emptied. When EC-NAPROXEN and NAPROXEN were given to fasted subjects (n=24) in a crossover study following 1 week of dosing, differences in time to peak plasma levels (T max ) were observed, but there were no differences in total absorption as measured by C max and AUC: EC-NAPROXEN* 500 mg bid EC-NAPROXEN* 500 mg bid C max (µg/mL) 94.9 (18%) 97.4 (13%) T max (hours) 4 (39%) 1.9 (61%) AUC 0–12 hr (µg·hr/mL) 845 (20%) 767 (15%) *Mean value (coefficient of variation) Antacid Effects When EC-NAPROXEN was given as a single dose with antacid (54 mEq buffering capacity), the peak plasma levels of naproxen were unchanged, but the time to peak was reduced (mean T max fasted 5.6 hours, mean T max with antacid 5 hours), although not significantly. [ see Drug Interactions (7) ]. Food Effects When EC-NAPROXEN was given as a single dose with food, peak plasma levels in most subjects were achieved in about 12 hours (range: 4 to 24 hours). Residence time in the small intestine until disintegration was independent of food intake. The presence of food prolonged the time the tablets remained in the stomach, time to first detectable serum naproxen levels, and time to maximal naproxen levels (T max ), but did not affect peak naproxen levels (C max ). Distribution Naproxen has a volume of distribution of 0.16 L/kg. At therapeutic levels naproxen is greater than 99% albumin-bound. At doses of naproxen greater than 500 mg/day there is less than proportional increase in plasma levels due to an increase in clearance caused by saturation of plasma protein binding at higher doses (average trough C ss 36.5, 49.2 and 56.4 mg/L with 500, 1,000 and 1,500 mg daily doses of naproxen, respectively). The naproxen anion has been found in the milk of lactating women at a concentration equivalent to approximately 1% of maximum naproxen concentration in plasma [see Use in Specific Populations ( 8.2 ) ] . Elimination Metabolism Naproxen is extensively metabolized in the liver to 6-0-desmethyl naproxen, and both parent and metabolites do not induce metabolizing enzymes. Both naproxen and 6-0-desmethyl naproxen are further metabolized to their respective acylglucuronide conjugated metabolites. Excretion The clearance of naproxen is 0.13 mL/min/kg. Approximately 95% of the naproxen from any dose is excreted in the urine, primarily as naproxen (<1%), 6-0-desmethyl naproxen (<1%) or their conjugates (66% to 92%). The plasma half-life of the naproxen anion in humans ranges from 12 to 17 hours. The corresponding half-lives of both naproxen’s metabolites and conjugates are shorter than 12 hours, and their rates of excretion have been found to coincide closely with the rate of naproxen clearance from the plasma. Small amounts, 3% or less of the administered dose, are excreted in the feces. In patients with renal failure metabolites may accumulate [ see Warnings and Precautions (5.6) ]. Specific Populations Pediatric: In pediatric patients aged 5 to 16 years with arthritis, plasma naproxen levels following a 5 mg/kg single dose of naproxen suspension [ see Dosage and Administration (2) ] were found to be similar to those found in normal adults following a 500 mg dose. The terminal half-life appears to be similar in pediatric and adult patients. Pharmacokinetic studies of naproxen were not performed in pediatric patients younger than 5 years of age. Pharmacokinetic parameters appear to be similar following administration of naproxen suspension or tablets in pediatric patients. Geriatric: Studies indicate that although total plasma concentration of naproxen is unchanged, the unbound plasma fraction of naproxen is increased in the elderly, although the unbound fraction is <1% of the total naproxen concentration. Unbound trough naproxen concentrations in elderly subjects have been reported to range from 0.12% to 0.19% of total naproxen concentration, compared with 0.05% to 0.075% in younger subjects. Hepatic Impairment: Naproxen pharmacokinetics have not been determined in subjects with hepatic insufficiency. Chronic alcoholic liver disease and probably other diseases with decreased or abnormal plasma proteins (albumin) reduce the total plasma concentration of naproxen, but the plasma concentration of unbound naproxen is increased. Renal Impairment: Naproxen pharmacokinetics have not been determined in subjects with renal insufficiency. Given that naproxen, its metabolites and conjugates are primarily excreted by the kidney, the potential exists for naproxen metabolites to accumulate in the presence of renal insufficiency. Elimination of naproxen is decreased in patients with severe renal impairment. Drug Interaction Studies Aspirin: When NSAIDs were administered with aspirin, the protein binding of NSAIDs were reduced, although the clearance of free NSAID was not altered. The clinical significance of this interaction is not known. See Table 1 for clinically significant drug interactions of NSAIDs with aspirin [see Drug Interactions (7) ].

    Pharmacokinetics Table

    EC-NAPROXEN* 500 mg bidEC-NAPROXEN* 500 mg bid
    Cmax (µg/mL)94.9 (18%)97.4 (13%)
    Tmax (hours)4 (39%)1.9 (61%)
    AUC0–12 hr (µg·hr/mL)845 (20%)767 (15%)

    Effective Time

    20220729

    Version

    3

    Dosage And Administration Table

    NAPROXEN Tablets 250 mg (one-half tablet) 500 mg twice daily
    NAPROXEN SODIUM 275 mg (one-half tablet) 550 mg twice daily
    EC-NAPROXEN 375 mg or 500 mg twice daily

    Dosage Forms And Strengths

    3 DOSAGE FORMS AND STRENGTHS NAPROXEN (naproxen) tablets: 500 mg: yellow, capsule-shaped, engraved with NPR LE 500 on one side and scored on the other. EC-NAPROXEN (naproxen) delayed-release tablets: 375 mg: white, oval biconvex coated tablets imprinted with NPR EC 375 on one side. EC-NAPROXEN (naproxen) delayed-release tablets: 500 mg: white, oblong coated tablets imprinted with NPR EC 500 on one side. NAPROXEN SODIUM (naproxen sodium) tablets: 550 mg: dark blue, oblong-shaped, engraved with NPS 550 on one side and scored on both sides. NAPROXEN® (naproxen) tablets: 500 mg EC-NAPROXEN® (naproxen) delayed-release tablets: 375 mg and 500 mg NAPROXEN SODIUM (naproxen sodium) tablets: 550 mg (contains 50 mg of sodium)

    Spl Product Data Elements

    NAPROXEN naproxen NAPROXEN NAPROXEN CROSCARMELLOSE SODIUM FERRIC OXIDE RED POVIDONE K90 MAGNESIUM STEARATE NPR;LE;500 EC-NAPROXEN naproxen NAPROXEN NAPROXEN CROSCARMELLOSE SODIUM POVIDONE K90 MAGNESIUM STEARATE METHACRYLIC ACID - METHYL METHACRYLATE COPOLYMER (1:1) TALC TRIETHYL CITRATE SODIUM HYDROXIDE WATER NPR;EC;375 EC-NAPROXEN naproxen NAPROXEN NAPROXEN CROSCARMELLOSE SODIUM POVIDONE K90 MAGNESIUM STEARATE METHACRYLIC ACID - METHYL METHACRYLATE COPOLYMER (1:1) TALC TRIETHYL CITRATE SODIUM HYDROXIDE WATER NPR;EC;500 NAPROXEN SODIUM DS naproxen sodium NAPROXEN SODIUM NAPROXEN MAGNESIUM STEARATE CELLULOSE, MICROCRYSTALLINE POVIDONE TALC NPS;550

    Carcinogenesis And Mutagenesis And Impairment Of Fertility

    13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility Carcinogenesis A 2-year study was performed in rats to evaluate the carcinogenic potential of naproxen at rat doses of 8, 16, and 24 mg/kg/day (0.05, 0.1, and 0.16 times the maximum recommended human daily dose [MRHD] of 1500 mg/day based on a body surface area comparison). No evidence of tumorigenicity was found. Mutagenesis Naproxen tested positive in the in vivo sister chromatid exchange assay for but was not mutagenic in the in vitro bacterial reverse mutation assay (Ames test). Impairment of Fertility Male rats were treated with 2, 5, 10, and 20 mg/kg naproxen by oral gavage for 60 days prior to mating and female rats were treated with the same doses for 14 days prior to mating and for the first 7 days of pregnancy. There were no adverse effects on fertility noted (up to 0.13 times the MRDH based on body surface area).

    Nonclinical Toxicology

    13 NONCLINICAL TOXICOLOGY 13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility Carcinogenesis A 2-year study was performed in rats to evaluate the carcinogenic potential of naproxen at rat doses of 8, 16, and 24 mg/kg/day (0.05, 0.1, and 0.16 times the maximum recommended human daily dose [MRHD] of 1500 mg/day based on a body surface area comparison). No evidence of tumorigenicity was found. Mutagenesis Naproxen tested positive in the in vivo sister chromatid exchange assay for but was not mutagenic in the in vitro bacterial reverse mutation assay (Ames test). Impairment of Fertility Male rats were treated with 2, 5, 10, and 20 mg/kg naproxen by oral gavage for 60 days prior to mating and female rats were treated with the same doses for 14 days prior to mating and for the first 7 days of pregnancy. There were no adverse effects on fertility noted (up to 0.13 times the MRDH based on body surface area).

    Application Number

    NDA020067

    Brand Name

    EC-NAPROXEN

    Generic Name

    naproxen

    Product Ndc

    69784-501

    Product Type

    HUMAN PRESCRIPTION DRUG

    Route

    ORAL

    Package Label Principal Display Panel

    PACKAGE LABEL.PRINCIPAL DISPLAY PANEL NDC 69097-505-01 Naproxen (naproxen tablets) 500 mg Each tablet contains 500 mg naproxen PHARMACIST: Dispense a Medication Guide with each precription. 100 Tablets Rx Only NDC 69097-501-01 Enteric Coated EC-Naproxen (naproxen delayed-release tablets) 375 mg Each tablet contains 375 mg naproxen PHARMACIST: Dispense a Medication Guide with each precription. 100 Tablets Rx Only NDC 69097-500-01 Enteric Coated EC-Naproxen (naproxen delayed-release tablets) 500 mg Each tablet contains 500 mg naproxen PHARMACIST: Dispense a Medication Guide with each precription. 100 Tablets Rx Only NDC 69097-550-01 Naproxen Sodium Tablets 550 mg Each tablet contains 550 mg naproxen sodium. PHARMACIST: Dispense a Medication Guide with each precription. 100 Tablets Rx Only image image image image

    Recent Major Changes

    Boxed Warning 05/2016 Warnings and Precautions ( 5.1 , 5.5 ) 05/2016

    Information For Patients

    17 PATIENT COUNSELING INFORMATION Advise the patient to read the FDA-approved patient labeling (Medication Guide) that accompanies each prescription dispensed. Inform patients, families, or their caregivers of the following information before initiating therapy with NAPROXEN Tablets, EC-NAPROXEN or NAPROXEN SODIUM and periodically during the course of ongoing therapy. Cardiovascular Thrombotic Events Advise patients to be alert for the symptoms of cardiovascular thrombotic events, including chest pain, shortness of breath, weakness, or slurring of speech, and to report any of these symptoms to their health care provider immediately [see Warnings and Precautions (5.1) ] . Gastrointestinal Bleeding, Ulceration, and Perforation Advise patients to report symptoms of ulcerations and bleeding, including epigastric pain, dyspepsia, melena, and hematemesis to their health care provider. In the setting of concomitant use of low-dose aspirin for cardiac prophylaxis, inform patients of the increased risk for the signs and symptoms of GI bleeding [see Warnings and Precautions (5.2) ] . Hepatotoxicity Inform patients of the warning signs and symptoms of hepatotoxicity (e.g., nausea, fatigue, lethargy, pruritus, diarrhea, jaundice, right upper quadrant tenderness, and “flu-like” symptoms). If these occur, instruct patients to stop NAPROXEN Tablets, EC-NAPROXEN or NAPROXEN SODIUM and seek immediate medical therapy [see Warnings and Precautions (5.3) ] . Heart Failure and Edema Advise patients to be alert for the symptoms of congestive heart failure including shortness of breath, unexplained weight gain, or edema and to contact their healthcare provider if such symptoms occur [see Warnings and Precautions (5.5) ] . Anaphylactic Reactions Inform patients of the signs of an anaphylactic reaction (e.g., difficulty breathing, swelling of the face or throat). Instruct patients to seek immediate emergency help if these occur [see Contraindications (4) and Warnings and Precautions (5.7) ] . Serious Skin Reactions Advise patients to stop NAPROXEN Tablets, EC-NAPROXEN or NAPROXEN SODIUM immediately if they develop any type of rash and to contact their healthcare provider as soon as possible [see Warnings and Precautions (5.9) ] . Female Fertility Advise females of reproductive potential who desire pregnancy that NSAIDs, including NAPROXEN Tablets, EC-NAPROXEN or NAPROXEN SODIUM, may be associated with a reversible delay in ovulation [see Use in Specific Populations (8.3) ]. Fetal Toxicity Inform pregnant women to avoid use of NAPROXEN Tablets, EC-NAPROXEN or NAPROXEN SODIUM and other NSAIDs starting at 30 weeks gestation because of the risk of the premature closing of the fetal ductus arteriosus [see Warnings and Precautions (5.10) and Use in Specific Populations (8.1) ] . Avoid Concomitant Use of NSAIDs Inform patients that the concomitant use of NAPROXEN Tablets, EC-NAPROXEN or NAPROXEN SODIUM with other NSAIDs or salicylates (e.g., diflunisal, salsalate) is not recommended due to the increased risk of gastrointestinal toxicity, and little or no increase in efficacy [see Warnings and Precautions (5.2) and Drug Interactions (7) ] . Alert patients that NSAIDs may be present in “over the counter” medications for treatment of colds, fever, or insomnia. Use of NSAIDS and Low-Dose Aspirin Inform patients not to use low-dose aspirin concomitantly with NAPROXEN Tablets, EC-NAPROXEN or NAPROXEN SODIUM until they talk to their healthcare provider [see Drug Interactions (7) ] . Manufactured for: Atnahs Pharma US Limited, Miles Gray Road, Basildon, Essex, SS14 3FR, United Kingdom Distributed by: Woodward Pharma Services LLC, Birmingham, MI 48009, United States

    Spl Medguide

    Medication Guide for Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) What is the most important information I should know about medicines called Non-Steroidal Anti- Inflammatory Drugs (NSAIDs)? NSAIDs can cause serious side effects, including: Increased risk of a heart attack or stroke that can lead to death. This risk may happen early in treatment and may increase: with increasing doses of NSAIDs with longer use of NSAIDs Do not take NSAIDs right before or after a heart surgery called a “coronary artery bypass graft (CABG).” Avoid taking NSAIDs after a recent heart attack, unless your healthcare provider tells you to. You may have an increased risk of another heart attack if you take NSAIDs after a recent heart attack. Increased risk of bleeding, ulcers, and tears (perforation) of the esophagus (tube leading from the mouth to the stomach), stomach and intestines: any time during use without warning symptoms that may cause death The risk of getting an ulcer or bleeding increases with: past history of stomach ulcers, or stomach or intestinal bleeding with use of NSAIDs taking medicines called “corticosteroids”, “anticoagulants”, “SSRIs”, or “SNRIs” increasing doses of NSAIDs longer use of NSAIDs smoking drinking alcohol older age poor health advanced liver disease bleeding problems NSAIDs should only be used: exactly as prescribed at the lowest dose possible for your treatment for the shortest time needed What are NSAIDs? NSAIDs are used to treat pain and redness, swelling, and heat (inflammation) from medical conditions such as different types of arthritis, menstrual cramps, and other types of short-term pain. Who should not take NSAIDs? Do not take NSAIDs: if you have had an asthma attack, hives, or other allergic reaction with aspirin or any other NSAIDs. right before or after heart bypass surgery. Before taking NSAIDs, tell your healthcare provider about all of your medical conditions, including if you: have liver or kidney problems have high blood pressure have asthma are pregnant or plan to become pregnant. Talk to your healthcare provider if you are considering taking NSAIDs during pregnancy. You should not take NSAIDs after 29 weeks of pregnancy. are breastfeeding or plan to breastfeed . Tell your healthcare provider about all of the medicines you take, including prescription or over-the-counter medicines, vitamins or herbal supplements. NSAIDs and some other medicines can interact with each other and cause serious side effects. Do not start taking any new medicine without talking to your healthcare provider first. What are the possible side effects of NSAIDs? NSAIDs can cause serious side effects, including: See “What is the most important information I should know about medicines called Nonsteroidal Anti-inflammatory Drugs (NSAIDs)? new or worse high blood pressure heart failure liver problems including liver failure kidney problems including kidney failure low red blood cells (anemia) life-threatening skin reactions life-threatening allergic reactions Other side effects of NSAIDs include: stomach pain, constipation, diarrhea, gas, heartburn, nausea, vomiting, and dizziness. Get emergency help right away if you have any of the following symptoms: shortness of breath or trouble breathing chest pain weakness in one part or side of your body slurred speech swelling of the face or throat Stop taking your NSAID and call your healthcare provider right away if you get any of the following symptoms: nausea more tired or weaker than usual diarrhea itching your skin or eyes look yellow indigestion or stomach pain flu-like symptoms vomit blood there is blood in your bowel movement or it is black and sticky like tar unusual weight gain skin rash or blisters with fever swelling of the arms, legs, hands and feet If you take too much of your NSAID, call your healthcare provider or get medical help right away. These are not all the possible side effects of NSAIDs. For more information, ask your healthcare provider or pharmacist about NSAIDs. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088. Other information about NSAIDs Aspirin is an NSAID medicine but it does not increase the chance of a heart attack. Aspirin can cause bleeding in the brain, stomach, and intestines. Aspirin can also cause ulcers in the stomach and intestines. Some NSAIDs are sold in lower doses without a prescription (over-the-counter). Talk to your healthcare provider before using over-the-counter NSAIDs for more than 10 days. General information about the safe and effective use of NSAIDs Medicines are sometimes prescribed for purposes other than those listed in a Medication Guide. Do not use NSAIDs for a condition for which it was not prescribed. Do not give NSAIDs to other people, even if they have the same symptoms that you have. It may harm them. If you would like more information about NSAIDs, talk with your healthcare provider. You can ask your pharmacist or healthcare provider for information about NSAIDs that is written for health professionals. Manufactured for: Atnahs Pharma US Limited, Miles Gray Road, Basildon, Essex, SS14 3FR, United Kingdom Distributed by: Woodward Pharma Services LLC, Birmingham, MI 48009, United States For more information, call 1-888-514-4727. This Medication Guide has been approved by the U.S. Food and Drug Administration. Issued or Revised: April 2019

    Clinical Studies

    14 CLINICAL STUDIES Naproxen has been studied in patients with rheumatoid arthritis, osteoarthritis, juvenile arthritis, ankylosing spondylitis, tendonitis and bursitis, and acute gout. Improvement in patients treated for rheumatoid arthritis was demonstrated by a reduction in joint swelling, a reduction in duration of morning stiffness, a reduction in disease activity as assessed by both the investigator and patient, and by increased mobility as demonstrated by a reduction in walking time. Generally, response to naproxen has not been found to be dependent on age, sex, severity or duration of rheumatoid arthritis. In patients with osteoarthritis, the therapeutic action of naproxen has been shown by a reduction in joint pain or tenderness, an increase in range of motion in knee joints, increased mobility as demonstrated by a reduction in walking time, and improvement in capacity to perform activities of daily living impaired by the disease. In a clinical trial comparing standard formulations of naproxen 375 mg twice a day (750 mg a day) vs 750 mg twice a day (1500 mg/day), 9 patients in the 750 mg group terminated prematurely because of adverse events. Nineteen patients in the 1500 mg group terminated prematurely because of adverse events. Most of these adverse events were gastrointestinal events. In clinical studies in patients with rheumatoid arthritis, osteoarthritis, and jpolyarticular juvenile idiopathic arthritis, naproxen has been shown to be comparable to aspirin and indomethacin in controlling the aforementioned measures of disease activity, but the frequency and severity of the milder gastrointestinal adverse effects (nausea, dyspepsia, heartburn) and nervous system adverse effects (tinnitus, dizziness, lightheadedness) were less in naproxen-treated patients than in those treated with aspirin or indomethacin. In patients with ankylosing spondylitis, naproxen has been shown to decrease night pain, morning stiffness and pain at rest. In double-blind studies the drug was shown to be as effective as aspirin, but with fewer side effects. In patients with acute gout, a favorable response to naproxen was shown by significant clearing of inflammatory changes (eg, decrease in swelling, heat) within 24 to 48 hours, as well as by relief of pain and tenderness. Naproxen has been studied in patients with mild to moderate pain secondary to postoperative, orthopedic, postpartum episiotomy and uterine contraction pain and dysmenorrhea. Onset of pain relief can begin within 1 hour in patients taking naproxen and within 30 minutes in patients taking naproxen sodium. Analgesic effect was shown by such measures as reduction of pain intensity scores, increase in pain relief scores, decrease in numbers of patients requiring additional analgesic medication, and delay in time to remedication. The analgesic effect has been found to last for up to 12 hours. Naproxen may be used safely in combination with gold salts and/or corticosteroids; however, in controlled clinical trials, when added to the regimen of patients receiving corticosteroids, it did not appear to cause greater improvement over that seen with corticosteroids alone. Whether naproxen has a “steroid-sparing” effect has not been adequately studied. When added to the regimen of patients receiving gold salts, naproxen did result in greater improvement. Its use in combination with salicylates is not recommended because there is evidence that aspirin increases the rate of excretion of naproxen and data are inadequate to demonstrate that naproxen and aspirin produce greater improvement over that achieved with aspirin alone. In addition, as with other NSAIDs, the combination may result in higher frequency of adverse events than demonstrated for either product alone. In 51 Cr blood loss and gastroscopy studies with normal volunteers, daily administration of 1000 mg of NAPROXEN (naproxen) or 1100 mg of NAPROXEN SODIUM (naproxen sodium) has been demonstrated to cause statistically significantly less gastric bleeding and erosion than 3250 mg of aspirin. Three 6-week, double-blind, multicenter studies with EC-NAPROXEN (naproxen) (375 or 500 mg twice a day, n=385) and NAPROXEN (375 or 500 mg bid, n=279) were conducted comparing EC-NAPROXEN with NAPROXEN, including 355 rheumatoid arthritis and osteoarthritis patients who had a recent history of NSAID-related GI symptoms. These studies indicated that EC-NAPROXEN and NAPROXEN showed no significant differences in efficacy or safety and had similar prevalence of minor GI complaints. Individual patients, however, may find one formulation preferable to the other. Five hundred and fifty-three patients received EC-NAPROXEN during long-term open-label trials (mean length of treatment was 159 days). The rates for clinically-diagnosed peptic ulcers and GI bleeds were similar to what has been historically reported for long-term NSAID use.

    Geriatric Use

    8.5 Geriatric Use The hepatic and renal tolerability of long-term naproxen administration was studied in two double-blind clinical trials involving 586 patients. Of the patients studied, 98 patients were age 65 and older and 10 of the 98 patients were age 75 and older. NAPROXEN was administered at doses of 375 mg twice daily or 750 mg twice daily for up to 6 months. Transient abnormalities of laboratory tests assessing hepatic and renal function were noted in some patients, although there were no differences noted in the occurrence of abnormal values among different age groups. Elderly patients, compared to younger patients, are at greater risk for NSAID-associated serious cardiovascular, gastrointestinal, and/or renal adverse reactions. If the anticipated benefit for the elderly patient outweighs these potential risks, start dosing at the low end of the dosing range, and monitor patients for adverse effects [ see Warnings and Precautions (5.1 , 5.2 , 5.3 , 5.6 , 5.13) ]. Studies indicate that although total plasma concentration of naproxen is unchanged, the unbound plasma fraction of naproxen is increased in the elderly. The clinical significance of this finding is unclear, although it is possible that the increase in free naproxen concentration could be associated with an increase in the rate of adverse events per a given dosage in some elderly patients. Caution is advised when high doses are required and some adjustment of dosage may be required in elderly patients. As with other drugs used in the elderly, it is prudent to use the lowest effective dose. Experience indicates that geriatric patients may be particularly sensitive to certain adverse effects of nonsteroidal anti-inflammatory drugs. Elderly or debilitated patients seem to tolerate peptic ulceration or bleeding less well when these events do occur. Most spontaneous reports of fatal GI events are in the geriatric population [ see Warnings and Precautions (5.2) ]. Naproxen is known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function [ see Clinical Pharmacology (12.3) ]. Geriatric patients may be at a greater risk for the development of a form of renal toxicity precipitated by reduced prostaglandin formation during administration of nonsteroidal anti-inflammatory drugs [ see Warnings and Precautions (5.6) ].

    Labor And Delivery

    8.2 Lactation Risk Summary The naproxen anion has been found in the milk of lactating women at a concentration equivalent to approximately 1% of maximum naproxen concentration in plasma. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and any potential adverse effects on the breastfed infant from the NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM or from the underlying maternal condition.

    Nursing Mothers

    8.3 Females and Males of Reproductive Potential Infertility Females Based on the mechanism of action, the use of prostaglandin-mediated NSAIDs, including NAPROXEN Tablets, EC-NAPROXEN, and NAPROXEN SODIUM, may delay or prevent rupture of ovarian follicles, which has been associated with reversible infertility in some women. Published animal studies have shown that administration of prostaglandin synthesis inhibitors has the potential to disrupt prostaglandin-mediated follicular rupture required for ovulation. Small studies in women treated with NSAIDs have also shown a reversible delay in ovulation. Consider withdrawal of NSAIDs, including NAPROXEN Tablets, EC-NAPROXEN and NAPROXEN SODIUM, in women who have difficulties conceiving or who are undergoing investigation of infertility.

    Pediatric Use

    8.4 Pediatric Use Safety and effectiveness in pediatric patients below the age of 2 years have not been established. Pediatric dosing recommendations for polyarticular juvenile idiopathic arthritis are based on well-controlled studies [ see Dosage and Administration (2) ]. There are no adequate effectiveness or dose-response data for other pediatric conditions, but the experience in polyarticular juvenile idiopathic arthritis and other use experience have established that single doses of 2.5 to 5 mg/kg as naproxen suspension, with total daily dose not exceeding 15 mg/kg/day, are well tolerated in pediatric patients over 2 years of age.

    Pregnancy

    8.1 Pregnancy Risk Summary Use of NSAIDs, including NAPROXEN Tablets, EC-NAPROXEN, and NAPROXEN SODIUM, during the third trimester of pregnancy increases the risk of premature closure of the fetal ductus arteriosus. Avoid use of NSAIDs, including NAPROXEN Tablets, EC-NAPROXEN, and NAPROXEN SODIUM, in pregnant women starting at 30 weeks of gestation (third trimester). There are no adequate and well-controlled studies of NAPROXEN Tablets, EC-NAPROXEN or NAPROXEN SODIUM in pregnant women. Data from observational studies regarding potential embryofetal risks of NSAID use in women in the first or second trimesters of pregnancy are inconclusive. In the general U.S. population, all clinically recognized pregnancies, regardless of drug exposure, have a background rate of 2-4% for major malformations, and 15-20% for pregnancy loss. In animal reproduction studies in rats, rabbits, and mice no evidence of teratogenicity or fetal harm when naproxen was administered during the period of organogenesis at doses 0.13, 0.26, and 0.6 times the maximum recommended human daily dose of 1500 mg/day, respectively [see Data] . Based on animal data, prostaglandins have been shown to have an important role in endometrial vascular permeability, blastocyst implantation, and decidualization. In animal studies, administration of prostaglandin synthesis inhibitors such as naproxen, resulted in increased pre- and post-implantation loss. Clinical Considerations Labor or Delivery There are no studies on the effects of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM during labor or delivery. In animal studies, NSAIDS, including naproxen, inhibit prostaglandin synthesis, cause delayed parturition, and increase the incidence of stillbirth. Data Human Data There is some evidence to suggest that when inhibitors of prostaglandin synthesis are used to delay preterm labor, there is an increased risk of neonatal complications such as necrotizing enterocolitis, patent ductus arteriosus, and intracranial hemorrhage. Naproxen treatment given in late pregnancy to delay parturition has been associated with persistent pulmonary hypertension, renal dysfunction, and abnormal prostaglandin E levels in preterm infants. Because of the known effects of nonsteroidal anti-inflammatory drugs on the fetal cardiovascular system (closure of ductus arteriosus), use during pregnancy (particularly starting at 30-weeks of gestation, or third trimester) should be avoided. Animal data Reproduction studies have been performed in rats at 20 mg/kg/day (0.13 times the maximum recommended human daily dose of 1500 mg/day based on body surface area comparison), rabbits at 20 mg/kg/day (0.26 times the maximum recommended human daily dose, based on body surface area comparison), and mice at 170 mg/kg/day (0.6 times the maximum recommended human daily dose based on body surface area comparison) with no evidence of impaired fertility or harm to the fetus due to the drug. Based on animal data, prostaglandins have been shown to have an important role in endometrial vascular permeability, blastocyst implantation, and decidualization. In animal studies, administration of prostaglandin synthesis inhibitors such as naproxen, resulted in increased pre- and post-implantation loss.

    Use In Specific Populations

    8 USE IN SPECIFIC POPULATIONS Pregnancy: Use of NSAIDs during the third trimester of pregnancy increases the risk of premature closure of the fetal ductus arteriosus. Avoid use of NSAIDs in pregnant women starting at 30 weeks gestation. (5.10 , 8.1) Infertility: NSAIDs are associated with reversible infertility. Consider withdrawal of NAPROXEN Tablets, EC-NAPROXEN and NAPROXEN SODIUM in women who have difficulties conceiving. (8.3) Renal Impairment: Naproxen-containing products are not recommended for use in patients with moderate to severe and severe renal impairment (creatinine clearance <30 mL/min). (8.7) 8.1 Pregnancy Risk Summary Use of NSAIDs, including NAPROXEN Tablets, EC-NAPROXEN, and NAPROXEN SODIUM, during the third trimester of pregnancy increases the risk of premature closure of the fetal ductus arteriosus. Avoid use of NSAIDs, including NAPROXEN Tablets, EC-NAPROXEN, and NAPROXEN SODIUM, in pregnant women starting at 30 weeks of gestation (third trimester). There are no adequate and well-controlled studies of NAPROXEN Tablets, EC-NAPROXEN or NAPROXEN SODIUM in pregnant women. Data from observational studies regarding potential embryofetal risks of NSAID use in women in the first or second trimesters of pregnancy are inconclusive. In the general U.S. population, all clinically recognized pregnancies, regardless of drug exposure, have a background rate of 2-4% for major malformations, and 15-20% for pregnancy loss. In animal reproduction studies in rats, rabbits, and mice no evidence of teratogenicity or fetal harm when naproxen was administered during the period of organogenesis at doses 0.13, 0.26, and 0.6 times the maximum recommended human daily dose of 1500 mg/day, respectively [see Data] . Based on animal data, prostaglandins have been shown to have an important role in endometrial vascular permeability, blastocyst implantation, and decidualization. In animal studies, administration of prostaglandin synthesis inhibitors such as naproxen, resulted in increased pre- and post-implantation loss. Clinical Considerations Labor or Delivery There are no studies on the effects of NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM during labor or delivery. In animal studies, NSAIDS, including naproxen, inhibit prostaglandin synthesis, cause delayed parturition, and increase the incidence of stillbirth. Data Human Data There is some evidence to suggest that when inhibitors of prostaglandin synthesis are used to delay preterm labor, there is an increased risk of neonatal complications such as necrotizing enterocolitis, patent ductus arteriosus, and intracranial hemorrhage. Naproxen treatment given in late pregnancy to delay parturition has been associated with persistent pulmonary hypertension, renal dysfunction, and abnormal prostaglandin E levels in preterm infants. Because of the known effects of nonsteroidal anti-inflammatory drugs on the fetal cardiovascular system (closure of ductus arteriosus), use during pregnancy (particularly starting at 30-weeks of gestation, or third trimester) should be avoided. Animal data Reproduction studies have been performed in rats at 20 mg/kg/day (0.13 times the maximum recommended human daily dose of 1500 mg/day based on body surface area comparison), rabbits at 20 mg/kg/day (0.26 times the maximum recommended human daily dose, based on body surface area comparison), and mice at 170 mg/kg/day (0.6 times the maximum recommended human daily dose based on body surface area comparison) with no evidence of impaired fertility or harm to the fetus due to the drug. Based on animal data, prostaglandins have been shown to have an important role in endometrial vascular permeability, blastocyst implantation, and decidualization. In animal studies, administration of prostaglandin synthesis inhibitors such as naproxen, resulted in increased pre- and post-implantation loss. 8.2 Lactation Risk Summary The naproxen anion has been found in the milk of lactating women at a concentration equivalent to approximately 1% of maximum naproxen concentration in plasma. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM and any potential adverse effects on the breastfed infant from the NAPROXEN Tablets, EC-NAPROXEN, or NAPROXEN SODIUM or from the underlying maternal condition. 8.3 Females and Males of Reproductive Potential Infertility Females Based on the mechanism of action, the use of prostaglandin-mediated NSAIDs, including NAPROXEN Tablets, EC-NAPROXEN, and NAPROXEN SODIUM, may delay or prevent rupture of ovarian follicles, which has been associated with reversible infertility in some women. Published animal studies have shown that administration of prostaglandin synthesis inhibitors has the potential to disrupt prostaglandin-mediated follicular rupture required for ovulation. Small studies in women treated with NSAIDs have also shown a reversible delay in ovulation. Consider withdrawal of NSAIDs, including NAPROXEN Tablets, EC-NAPROXEN and NAPROXEN SODIUM, in women who have difficulties conceiving or who are undergoing investigation of infertility. 8.4 Pediatric Use Safety and effectiveness in pediatric patients below the age of 2 years have not been established. Pediatric dosing recommendations for polyarticular juvenile idiopathic arthritis are based on well-controlled studies [ see Dosage and Administration (2) ]. There are no adequate effectiveness or dose-response data for other pediatric conditions, but the experience in polyarticular juvenile idiopathic arthritis and other use experience have established that single doses of 2.5 to 5 mg/kg as naproxen suspension, with total daily dose not exceeding 15 mg/kg/day, are well tolerated in pediatric patients over 2 years of age. 8.5 Geriatric Use The hepatic and renal tolerability of long-term naproxen administration was studied in two double-blind clinical trials involving 586 patients. Of the patients studied, 98 patients were age 65 and older and 10 of the 98 patients were age 75 and older. NAPROXEN was administered at doses of 375 mg twice daily or 750 mg twice daily for up to 6 months. Transient abnormalities of laboratory tests assessing hepatic and renal function were noted in some patients, although there were no differences noted in the occurrence of abnormal values among different age groups. Elderly patients, compared to younger patients, are at greater risk for NSAID-associated serious cardiovascular, gastrointestinal, and/or renal adverse reactions. If the anticipated benefit for the elderly patient outweighs these potential risks, start dosing at the low end of the dosing range, and monitor patients for adverse effects [ see Warnings and Precautions (5.1 , 5.2 , 5.3 , 5.6 , 5.13) ]. Studies indicate that although total plasma concentration of naproxen is unchanged, the unbound plasma fraction of naproxen is increased in the elderly. The clinical significance of this finding is unclear, although it is possible that the increase in free naproxen concentration could be associated with an increase in the rate of adverse events per a given dosage in some elderly patients. Caution is advised when high doses are required and some adjustment of dosage may be required in elderly patients. As with other drugs used in the elderly, it is prudent to use the lowest effective dose. Experience indicates that geriatric patients may be particularly sensitive to certain adverse effects of nonsteroidal anti-inflammatory drugs. Elderly or debilitated patients seem to tolerate peptic ulceration or bleeding less well when these events do occur. Most spontaneous reports of fatal GI events are in the geriatric population [ see Warnings and Precautions (5.2) ]. Naproxen is known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function [ see Clinical Pharmacology (12.3) ]. Geriatric patients may be at a greater risk for the development of a form of renal toxicity precipitated by reduced prostaglandin formation during administration of nonsteroidal anti-inflammatory drugs [ see Warnings and Precautions (5.6) ]. 8.6 Hepatic Impairment Caution is advised when high doses are required and some adjustment of dosage may be required in these patients. It is prudent to use the lowest effective dose [ see Clinical Pharmacology (12.3) ]. 8.7 Renal Impairment Naproxen-containing products are not recommended for use in patients with moderate to severe and severe renal impairment (creatinine clearance <30 mL/min) [ see Warnings and Precautions (5.6) , Clinical Pharmacology (12.3) ].

    How Supplied

    16 HOW SUPPLIED/STORAGE AND HANDLING NAPROXEN (naproxen) tablets 500 mg: yellow, capsule-shaped tablets, engraved with NPR LE 500 on one side and scored on the other. Packaged in light-resistant bottles of 100. Supplied as: NDC 69784-505-01 100’s (bottle) Store at 15°C to 30°C (59°F to 86°F) in well-closed containers; dispense in light-resistant containers. EC-NAPROXEN (naproxen) delayed-release tablets 375 mg: white, oval biconvex coated tablets imprinted with NPR EC 375 on one side. Packaged in light-resistant bottles of 100. Supplied as: NDC 69784-501-01 100’s (bottle) 500 mg: white, oblong coated tablets imprinted with NPR EC 500 on one side. Packaged in light-resistant bottles of 100. Supplied as: NDC 69784-500-01 100’s (bottle) Store at 15°C to 30°C (59°F to 86°F) in well-closed containers; dispense in light-resistant containers. NAPROXEN SODIUM (naproxen sodium) Tablets 550 mg: dark blue, oblong-shaped tablets, engraved with NPS 550 on one side and scored on both sides. Packaged in bottles of 100. Supplied as: NDC 69784-550-01 100’s (bottle) Store at 15° to 30°C (59° to 86°F) in well-closed containers.

    Boxed Warning

    WARNING: RISK OF SERIOUS CARDIOVASCULAR AND GASTROINTESTINAL EVENTS Cardiovascular Thrombotic Events Nonsteroidal anti-inflammatory drugs (NSAIDs) cause an increased risk of serious cardiovascular thrombotic events, including myocardial infarction and stroke, which can be fatal. This risk may occur early in treatment and may increase with duration of use [ see Warnings and Precautions (5.1) ]. Naproxen tablets are contraindicated in the setting of coronary artery bypass graft (CABG) surgery [ see Contraindications (4) , Warnings and Precautions (5.1) ]. Gastrointestinal Bleeding, Ulceration, and Perforation NSAIDs cause an increased risk of serious gastrointestinal (GI) adverse events including bleeding, ulceration, and perforation of the stomach or intestines, which can be fatal. These events can occur at any time during use and without warning symptoms. Elderly patients and patients with a prior history of peptic ulcer disease and/or GI bleeding are at greater risk for serious GI events [ see Warnings and Precautions (5.2) ]. WARNING: RISK OF SERIOUS CARDIOVASCULAR AND GASTROINTESTINAL EVENTS See full prescribing information for complete boxed warning. Nonsteroidal anti-inflammatory drugs (NSAIDs) cause an increased risk of serious cardiovascular thrombotic events, including myocardial infarction and stroke, which can be fatal. This risk may occur early in treatment and may increase with duration of use. (5.1) NAPROXEN Tablets, EC-NAPROXEN and NAPROXEN SODIUM are contraindicated in the setting of coronary artery bypass graft (CABG) surgery. (4 , 5.1) NSAIDs cause an increased risk of serious gastrointestinal (GI) adverse events including bleeding, ulceration, and perforation of the stomach or intestines, which can be fatal. These events can occur at any time during use and without warning symptoms. Elderly patients and patients with a prior history of peptic ulcer disease and/or GI bleeding are at greater risk for serious GI events. (5.2)

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