Carbamazepine

ADVERSE REACTIONS If adverse reactions are of such severity that the drug must be discontinued, the physician must be aware that abrupt discontinuation of any anticonvulsant drug in a responsive epileptic patient may lead to seizures or even status epilepticus with its life-threatening hazards. The most severe adverse reactions have been observed in the hemopoietic system and skin (see BOXED WARNING), the liver, and the cardiovascular system. The most frequently observed adverse reactions, particularly during the initial phases of therapy, are dizziness, drowsiness, unsteadiness, nausea, and vomiting. To minimize the possibility of such reactions, therapy should be initiated at the lowest dosage recommended. The following additional adverse reactions have been reported: Hemopoietic System : Aplastic anemia, agranulocytosis, pancytopenia, bone marrow depression, thrombocytopenia, leukopenia, leukocytosis, eosinophilia, acute intermittent porphyria, variegate porphyria, porphyria cutanea tarda. Skin : Toxic epidermal necrolysis (TEN) and Stevens-Johnson syndrome (SJS) (see BOXED WARNING), Acute Generalized Exanthematous Pustulosis (AGEP), pruritic and erythematous rashes, urticaria, photosensitivity reactions, alterations in skin pigmentation, exfoliative dermatitis, erythema multiforme and nodosum, purpura, aggravation of disseminated lupus erythematosus, alopecia, diaphoresis, onychomadesis and hirsutism. In certain cases, discontinuation of therapy may be necessary. Cardiovascular System : Congestive heart failure, edema, aggravation of hypertension, hypotension, syncope and collapse, aggravation of coronary artery disease, arrhythmias and AV block, thrombophlebitis, thromboembolism (e.g., pulmonary embolism), and adenopathy or lymphadenopathy. Some of these cardiovascular complications have resulted in fatalities. Myocardial infarction has been associated with other tricyclic compounds. Liver : Abnormalities in liver function tests, cholestatic and hepatocellular jaundice, hepatitis, very rare cases of hepatic failure. Pancreatic : Pancreatitis. Respiratory System : Pulmonary hypersensitivity characterized by fever, dyspnea, pneumonitis, or pneumonia. Genitourinary System : Urinary frequency, acute urinary retention, oliguria with elevated blood pressure, azotemia, renal failure, and impotence. Albuminuria, glycosuria, elevated BUN, and microscopic deposits in the urine have also been reported. There have been rare reports of impaired male fertility and/or abnormal spermatogenesis. Testicular atrophy occurred in rats receiving carbamazepine orally from 4 to 52 weeks at dosage levels of 50 to 400 mg/kg/day. Additionally, rats receiving carbamazepine in the diet for 2 years at dosage levels of 25, 75, and 250 mg/kg/day had a dose-related incidence of testicular atrophy and aspermatogenesis. In dogs, it produced a brownish discoloration, presumably a metabolite, in the urinary bladder at dosage levels of 50 mg/kg and higher. Relevance of these findings to humans is unknown. Nervous System : Dizziness, drowsiness, disturbances of coordination, confusion, headache, fatigue, blurred vision, visual hallucinations, transient diplopia, oculomotor disturbances, nystagmus, speech disturbances, abnormal involuntary movements, peripheral neuritis and paresthesias, depression with agitation, talkativeness, tinnitus, hyperacusis, neuroleptic malignant syndrome. There have been reports of associated paralysis and other symptoms of cerebral arterial insufficiency, but the exact relationship of these reactions to the drug has not been established. Isolated cases of neuroleptic malignant syndrome have been reported both with and without concomitant use of psychotropic drugs. Digestive System : Nausea, vomiting, gastric distress and abdominal pain, diarrhea, constipation, anorexia, and dryness of the mouth and pharynx, including glossitis and stomatitis. Eyes : Scattered punctate cortical lens opacities, increased intraocular pressure (see WARNINGS, General) as well as conjunctivitis, have been reported. Although a direct causal relationship has not been established, many phenothiazines and related drugs have been shown to cause eye changes Musculoskeletal System : Aching joints and muscles, and leg cramps. Metabolism : Fever and chills. Hyponatremia (see WARNINGS, General).Decreased levels of plasma calcium have been reported. Osteoporosis has been reported. Isolated cases of a lupus erythematosus-like syndrome have been reported. There have been occasional reports of elevated levels of cholesterol, HDL cholesterol, and triglycerides in patients taking anticonvulsants. A case of aseptic meningitis, accompanied by myoclonus and peripheral eosinophilia, has been reported in a patient taking carbamazepine in combination with other medications. The patient was successfully dechallenged, and the meningitis reappeared upon rechallenge with carbamazepine.

CONTRAINDICATIONS Carbamazepine should not be used in patients with a history of previous bone marrow depression, hypersensitivity to the drug, or known sensitivity to any of the tricyclic compounds, such as amitriptyline, desipramine, imipramine, protriptyline, nortriptyline, etc. Likewise, on theoretical grounds its use with monoamine oxidase (MAO) inhibitors is not recommended. Before administration of carbamazepine, MAO inhibitors should be discontinued for a minimum of 14 days, or longer if the clinical situation permits. Coadministration of carbamazepine and nefazodone may result in insufficient plasma concentrations of nefazodone and its active metabolite to achieve a therapeutic effect. Coadministration of carbamazepine with nefazodone is contraindicated.

DESCRIPTION Carbamazepine Tablets, carbamazepine USP, is an anticonvulsant and specific analgesic for trigeminal neuralgia, available for oral administration as tablets of 100 mg and 200 mg. Its chemical name is 5H-dibenz[b,f ]azepine-5-carboxamide, and its structural formula is: Carbamazepine USP is a white to off-white powder, practically insoluble in water and soluble in alcohol and in acetone. Its molecular weight is 236.27. Inactive Ingredients Tablets: pregelatinized maize starch, FD & C red 40, croscarmellose sodium, colloidal silicon dioxide and magnesium stearate. "Meets USP Dissolution Test 2" carbamazepine-strecture

DOSAGE AND ADMINISTRATION (SEE TABLE BELOW) Carbamazepine suspension in combination with liquid chlorpromazine or thioridazine results in precipitate formation, and, in the case of chlorpromazine, there has been a report of patient passing an orange rubbery precipitate in the stool following coadministration of the two drugs (see PRECAUTIONS, Drug Interactions). Because the extent to which this occurs with other liquid medications is not known, Carbamazepine suspension should not be administered simultaneously with other liquid medications or diluents. Monitoring of blood levels has increased the efficacy and safety of anticonvulsants (see PRECAUTIONS, Laboratory Tests). Dosage should be adjusted to the needs of the individual patient. A low initial daily dosage with a gradual increase is advised. As soon as adequate control is achieved, the dosage may be reduced very gradually to the minimum effective level. Medication should be taken with meals. Since a given dose of Carbamazepine suspension will produce higher peak levels than the same dose given as the tablet, it is recommended to start with low doses (children 6 to 12 years: ½ teaspoon four times a day and to increase slowly to avoid unwanted side effects. Conversion of patients from oral Carbamazepine tablets to Carbamazepine suspension: Patients should be converted by administering the same number of mg per day in smaller, more frequent doses (i.e., twice a day tablets to three times a day suspension). Carbamazepine -XR is an extended-release formulation for twice a day administration. When converting patients from Carbamazepine conventional tablets to Carbamazepine -XR, the same total daily mg dose of Carbamazepine -XR should be administered. Carbamazepine -XR tablets must be swallowed whole and never crushed or chewed. Carbamazepine -XR tablets should be inspected for chips or cracks. Damaged tablets, or tablets without a release portal, should not be consumed. Carbamazepine -XR tablet coating is not absorbed and is excreted in the feces; these coatings may be noticeable in the stool. Epilepsy (SEE INDICATIONS AND USAGE) Adults and children over 12 years of age-Initial : Either 200 mg twice a day for tablets and XR tablets, or 1 teaspoon four times a day for suspension (400 mg/day). Increase at weekly intervals by adding up to 200 mg/day using a twice a day regimen of Carbamazepine -XR or a three times a day or four times a day regimen of the other formulations until the optimal response is obtained. Dosage generally should not exceed 1000 mg daily in children 12 to 15 years of age, and 1200 mg daily in patients above 15 years of age. Doses up to 1600 mg daily have been used in adults in rare instances. Maintenance : Adjust dosage to the minimum effective level, usually 800 to 1200 mg daily. Children 6 to 12 years of age-Initial : Either 100 mg twice a day for tablets or XR tablets, or ½ teaspoon four times a day for suspension (200 mg/day). Increase at weekly intervals by adding up to 100 mg/day using a twice a day regimen of Carbamazepine -XR or a three times a day or four times a day regimen of the other formulations until the optimal response is obtained.. Dosage generally should not exceed 1000 mg daily. Maintenance : Adjust dosage to the minimum effective level, usually 400 to 800 mg daily. Children under 6 years of age-Initial : 10 to 20 mg/kg/day twice a day or three times a day as tablets, or four times a day as suspension . Increase weekly to achieve optimal clinical response administered three times a day or four times a day. Maintenance : Ordinarily, optimal clinical response is achieved at daily doses below 35 mg/kg. If satisfactory clinical response has not been achieved, plasma levels should be measured to determine whether or not they are in the therapeutic range. No recommendation regarding the safety of carbamazepine for use at doses above 35 mg/kg/24 hours can be made. Combination Therapy : Carbamazepine may be used alone or with other anticonvulsants. When added to existing anticonvulsant therapy, the drug should be added gradually while the other anticonvulsants are maintained or gradually decreased, except phenytoin, which may have to be increased (see PRECAUTIONS, Drug Interactions, and Pregnancy). Trigeminal Neuralgia (SEE INDICATIONS AND USAGE) Initial : On the first day, either 100 mg twice a day for tablets or XR tablets or ½ teaspoon four times a day for suspension, for a total daily dose of 200 mg. This daily dose may be increased by up to 200 mg/day using increments of 100 mg every 12 hours for tablets or XR tablets, or 50 mg (½ teaspoon) four times a day for suspension, only as needed to achieve freedom from pain. Do not exceed 1200 mg daily. Maintenance : Control of pain can be maintained in most patients with 400 to 800 mg daily. However, some patients may be maintained on as little as 200 mg daily, while others may require as much as 1200 mg daily. At least once every 3 months throughout the treatment period, attempts should be made to reduce the dose to the minimum effective level or even to discontinue the drug. Dosage Information Initial Dose Subsequent Dose MaximumDaily Dose Indication Tablet* XR † Suspension Tablet* XR † Suspension Tablet* XR † Suspension Epilepsy Under 6 yr 10-20 mg/kg/day twice a day or 3 times of day 10-20 mg/kg/day 4 times a day Increase weekly to achieve optimal clinical response, 3 times a day or 4 times a day Increase weekly to achieve optimal clinical response, 3 times a day or 4 times a day 35mg/kg/24hr (see Dosage and Administration section above) 35 mg/kg/24 hr (see Dosage and Administration section above) 6-12 yr 100 mg twice a day (200 mg/day) 100 mg twice a day (200 mg/day) ½ tsp 4 times a day (200 mg/day) Add up to 100 mg/day at weekly intervals 3 times a day or 4 times a day Add 100 mg/day at weekly intervals, twice a day Add up to 1 tsp (100 mg)/day at weekly intervals, 3 times a day or 4 times a day 1000mg/24 hr Over 12 yr 200 mg twice a day(400 mg/day) 200 mg twice a day (400 mg/day) 1 tsp 4 times a day (400 mg/day) Add up to 200 mg/day at weekly intervals, 3 times a day or 4 times a day Add up to 200 mg/day at weekly intervals, twice a day Add up to 2 tsp (200 mg)/day at weekly intervals, 3 times a day or 4 times a day 1000 mg/24 hr (12-15 yr) 1200 mg/24 hr (>15 yr) 1600 mg/24 hr (adults, in rare instances) Trigeminal Neuralgia 100 mg twice a day(200 mg/day) 100 mg twice a day (200 mg/day) ½ tsp 4 times a day (200 mg/day) Add up to 200 mg/day in increments of 100 mg every 12 hr Add up to 200 mg/day in increments of 100 mg every 12 hr Add up to 2 tsp (200 mg)/day in increments of 50 mg (½ tsp) 4 times a day 1200mg/24 hr * Tablet = conventional tablets † XR = Tegretol-XR extended-release tablets

INDICATIONS AND USAGE Epilepsy Carbamazepine is indicated for use as an anticonvulsant drug. Evidence supporting efficacy of carbamazepine as an anticonvulsant was derived from active drug-controlled studies that enrolled patients with the following seizure types: 1. Partial seizures with complex symptomatology (psychomotor, temporal lobe). Patients with these seizures appear to show greater improvement than those with other types. 2. Generalized tonic-clonic seizures (grand mal). 3. Mixed seizure patterns which include the above, or other partial or generalized seizures. Absence seizures (petit mal) do not appear to be controlled by carbamazepine (see PRECAUTIONS , General). Trigeminal Neuralgia Carbamazepine is indicated in the treatment of the pain associated with true trigeminal neuralgia. Beneficial results have also been reported in glossopharyngeal neuralgia. This drug is not a simple analgesic and should not be used for the relief of trivial aches or pains.

DRUG ABUSE AND DEPENDENCE No evidence of abuse potential has been associated with carbamazepine nor is there evidence of psychological or physical dependence in humans.

OVERDOSAGE Acute Toxicity Lowest known lethal dose: adults, 3.2 g (a 24-year-old woman died of a cardiac arrest and a 24-year-old man died of pneumonia and hypoxic encephalopathy); children, 4 g (a 14-year-old girl died of a cardiac arrest), 1.6 g (a 3-year-old girl died of aspiration pneumonia). Oral LD 50 in animals (mg/kg): mice, 1100 to 3750; rats, 3850 to 4025; rabbits, 1500 to 2680; guinea pigs, 920. Signs and Symptoms The first signs and symptoms appear after 1 to 3 hours. Neuromuscular disturbances are the most prominent. Cardiovascular disorders are generally milder, and severe cardiac complications occur only when very high doses (greater than 60 g) have been ingested. Respiration : Irregular breathing, respiratory depression. Cardiovascular System : Tachycardia, hypotension or hypertension, shock, conduction disorders. Nervous System and Muscles : Impairment of consciousness ranging in severity to deep coma. Convulsions, especially in small children. Motor restlessness, muscular twitching, tremor, athetoid movements, opisthotonos, ataxia, drowsiness, dizziness, mydriasis, nystagmus, adiadochokinesia, ballism, psychomotor disturbances, dysmetria. Initial hyperreflexia, followed by hyporeflexia. Gastrointestinal Tract : Nausea, vomiting. Kidneys and Bladder : Anuria or oliguria, urinary retention. Laboratory Findings : Isolated instances of overdosage have included leukocytosis, reduced leukocyte count, glycosuria, and acetonuria. EEG may show dysrhythmias. Combined Poisoning : When alcohol, tricyclic antidepressants, barbiturates, or hydantoins are taken at the same time, the signs and symptoms of acute poisoning with carbamazepine may be aggravated or modified. Treatment The prognosis in cases of severe poisoning is critically dependent upon prompt elimination of the drug, which may be achieved by inducing vomiting, irrigating the stomach, and by taking appropriate steps to diminish absorption. If these measures cannot be implemented without risk on the spot, the patient should be transferred at once to a hospital, while ensuring that vital functions are safeguarded. There is no specific antidote. Elimination of the Drug : Induction of vomiting. Gastric lavage. Even when more than 4 hours have elapsed following ingestion of the drug, the stomach should be repeatedly irrigated, especially if the patient has also consumed alcohol. Measures to Reduce Absorption : Activated charcoal, laxatives. Measures to Accelerate Elimination : Forced diuresis. Dialysis is indicated only in severe poisoning associated with renal failure. Replacement transfusion is indicated in sever poisoning in small children. Respiratory Depression : Keep the airways free; resort, if necessary, to endotracheal intubation, artificial respiration, and administration of oxygen. Hypotension, Shock : Keep the patient's legs raised and administer a plasma expander. If blood pressure fails to rise despite measures taken to increase plasma volume, use of vasoactive substances should be considered. Convulsions : Diazepam or barbiturates. Warning : Diazepam or barbiturates may aggravate respiratory depression (especially in children), hypotension, and coma. However, barbiturates should not be used if drugs that inhibit monoamine oxidase have also been taken by the patient either in overdosage or in recent therapy (within 1 week). Surveillance : Respiration, cardiac function (ECG monitoring), blood pressure, body temperature, pupillary reflexes, and kidney and bladder function should be monitored for several days. Treatment of Blood Count Abnormalities : If evidence of significant bone marrow depression develops, the following recommendations are suggested: (1) stop the drug, (2) perform daily CBC, platelet, and reticulocyte counts, (3) do a bone marrow aspiration and trephine biopsy immediately and repeat with sufficient frequency to monitor recovery. Special periodic studies might be helpful as follows: (1) white cell and platelet antibodies, (2) 59 Fe-ferrokinetic studies, (3) peripheral blood cell typing, (4) cytogenetic studies on marrow and peripheral blood, (5) bone marrow culture studies for colony-forming units, (6) hemoglobin electrophoresis for A 2 and F hemoglobin, and (7) serum folic acid and B 12 levels. A fully developed aplastic anemia will require appropriate, intensive monitoring and therapy, for which specialized consultation should be sought.

Drug Interactions There has been a report of a patient who passed an orange rubbery precipitate in his stool the day after ingesting carbamazepine suspension immediately followed by Thorazine solution. Subsequent testing has shown that mixing carbamazepine suspension and chlorpromazine solution (both generic and brand name) as well as carbamazepine suspension and liquid Mellaril, resulted in the occurrence of this precipitate. Because the extent to which this occurs with other liquid medications is not known, carbamazepine suspension should not be administered simultaneously with other liquid medicinal agents or diluents (see DOSAGE AND ADMINISTRATION). Clinically meaningful drug interactions have occurred with concomitant medications and include (but are not limited to) the following: Agents That May Affect Carbamazepine Plasma Levels When carbamazepine is given with drugs that can increase or decrease carbamazepine levels, close monitoring of carbamazepine levels is indicated and dosage adjustment may be required. Agents That Increase Carbamazepine Levels CYP3A4 inhibitors inhibit carbamazepine metabolism and can thus increase plasma carbamazepine levels. Drugs that have been shown, or would be expected, to increase plasma carbamazepine levels include aprepitant, cimetidine, ciprofloxacin, danazol, diltiazem, macrolides, erythromycin, troleandomycin, clarithromycin, fluoxetine, fluvoxamine, trazodone, olanzapine, loratadine, terfenadine, omeprazole, oxybutynin, dantrolene, isoniazid, niacinamide, nicotinamide, ibuprofen, propoxyphene, azoles (e.g., ketaconazole, itraconazole, fluconazole, voriconazole), acetazolamide, verapamil, ticlopidine, grapefruit juice, and protease inhibitors. Human microsomal epoxide hydrolase has been identified as the enzyme responsible for the formation of the 10, 11-transdiol derivative from carbamazepine-10,11 epoxide. Coadministration of inhibitors of human microsomal epoxide hydrolase may result in increased carbamazepine-10, 11 epoxide plasma concentrations. Accordingly, the dosage of carbamazepine should be adjusted and/or the plasma levels monitored when used concomitantly with loxapine, quetiapine, or valproic acid. Agents That Decrease Carbamazepine Levels CYP3A4 inducers can increase the rate of carbamazepine metabolism. Drugs that have been shown, or that would be expected, to decrease plasma carbamazepine levels include cisplatin, doxorubicin HCl, felbamate, fosphenytoin, rifampin, phenobarbital, phenytoin, primidone, methsuximide, theophylline, aminophylline. Effect of Carbamazepine on Plasma Levels of Concomitant Agents Decreased Levels of Concomitant Medications Carbamazepine is a potent inducer of hepatic 3A4 and is also known to be an inducer of CYP1A2, 2B6, 2C9/19 and may therefore reduce plasma concentrations of co-medications mainly metabolized by CYP 1A2, 2B6, 2C9/19 and 3A4, through induction of their metabolism. When used concomitantly with carbamazepine, monitoring of concentrations or dosage adjustment of these agents may be necessary: When carbamazepine is added to aripiprazole, the aripiprazole dose should be doubled. Additional dose increases should be based on clinical evaluation. If carbamazepine is later withdrawn, the aripiprazole dose should be reduced. When carbamazepine is used with tacrolimus, monitoring of tacrolimus blood concentrations and appropriate dosage adjustments are recommended. The use of concomitant strong CYP3A4 inducers such as carbamazepine should be avoided with temsirolimus. If patients must be coadministered carbamazepine with temsirolimus, an adjustment of temsirolimus dosage should be considered. The use of carbamazepine with lapatinib should generally be avoided. If carbamazepine is started in a patient already taking lapatinib, the dose of lapatinib should be gradually titrated up. If carbamazepine is discontinued, the lapatinib dose should be reduced. Concomitant use of carbamazepine with nefazodone results in plasma concentrations of nefazodone and its active metabolite insufficient to achieve a therapeutic effect. Coadministration of carbamazepine with nefazodone is contraindicated (see CONTRAINDICATIONS ). Monitor concentrations of valproate when carbamazepine is introduced or withdrawn in patients using valproic acid. In addition, carbamazepine causes, or would be expected to cause, decreased levels of the following drugs, for which monitoring of concentrations or dosage adjustment may be necessary: acetaminophen, albendazole, alprazolam, aprepitant, buprenorphone, bupropion, citalopram, clonazepam, clozapine, corticosteroids (e.g., prednisolone, dexamethasone), cyclosporine, dicumarol, dihydropyridine calcium channel blockers (e.g., felodipine), doxycycline, ethosuximide, everolimus, haloperidol, imatinib, itraconazole, lamotrigine, levothyroxine, methadone, methsuximide, mianserin, midazolam, olanzapine, oral and other hormonal contraceptives, oxcarbazepine, paliperidone, phensuximide, phenytoin, praziquantel, protease inhibitors, risperidone, sertraline, sirolimus, tadalafil, theophylline, tiagabine, topiramate, tramadol, trazodone, tricyclic antidepressants (e.g., imipramine, amitriptyline, nortriptyline), valproate, warfarin, ziprasidone, zonisamide. Other Drug Interactions Cyclophosphamide is an inactive prodrug and is converted to its active metabolite in part by CYP3A. The rate of metabolism and the leukopenic activity of cyclophosphamide are reportedly increased by chronic coadministration of CYP3A4 inducers. There is a potential for increased cyclophosphamide toxicity when coadministered with carbamazepine. Concomitant administration of carbamazepine and lithium may increase the risk of neurotoxic side effects. Concomitant use of carbamazepine and isoniazid has been reported to increase isoniazid-induced hepatotoxicity. Alterations of thyroid function have been reported in combination therapy with other anticonvulsant medications. Concomitant use of carbamazepine with hormonal contraceptive products (e.g., oral, and levonorgestrel subdermal implant contraceptives) may render the contraceptives less effective because the plasma concentrations of the hormones may be decreased. Breakthrough bleeding and unintended pregnancies have been reported. Alternative or back-up methods of contraception should be considered. Resistance to the neuromuscular blocking action of the nondepolarizing neuromuscular blocking agents pancuronium, vecuronium, rocuronium and cisatracurium has occurred in patients chronically administered carbamazepine. Whether or not carbamazepine has the same effect on other non-depolarizing agents is unknown. Patients should be monitored closely for more rapid recovery from neuromuscular blockade than expected, and infusion rate requirements may be higher. Concomitant use of carbamazepine with rivaroxaban, apixaban, dabigatran, and edoxaban (direct acting oral anticoagulants) is expected to result in decreased plasma concentration of these anticoagulants that may be insufficient to achieve the intended therapeutic effect. In general, coadministration of carbamazepine with rivaroxaban, apixaban, dabigatran, and edoxaban should be avoided. Carcinogenesis, Mutagenesis, Impairment of Fertility Carbamazepine, when administered to Sprague-Dawley rats for two years in the diet at doses of 25, 75, and 250 mg/kg/day, resulted in a dose-related increase in the incidence of hepatocellular tumors in females and of benign interstitial cell adenomas in the testes of males. Carbamazepine must, therefore, be considered to be carcinogenic in Sprague-Dawley rats. Bacterial and mammalian mutagenicity studies using carbamazepine produced negative results. The significance of these findings relative to the use of carbamazepine in humans is, at present, unknown. Usage in Pregnancy (see WARNINGS). Labor and Delivery The effect of carbamazepine on human labor and delivery is unknown. Nursing Mothers Carbamazepine and its epoxide metabolite are transferred to breast milk. The ratio of the concentration in breast milk to that in maternal plasma is about 0.4 for carbamazepine and about 0.5 for the epoxide. The estimated doses given to the newborn during breastfeeding are in the range of 2 to 5 mg daily for carbamazepine and 1 to 2 mg daily for the epoxide. Because of the potential for serious adverse reactions in nursing infants from carbamazepine, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother. Pediatric Use Substantial evidence of carbamazepine's effectiveness for use in the management of children with epilepsy (see INDICATIONS AND USAGE for specific seizure types) is derived from clinical investigations performed in adults and from studies in several in vitro systems which support the conclusion that (1) the pathogenetic mechanisms underlying seizure propagation are essentially identical in adults and children, and (2) the mechanism of action of carbamazepine in treating seizures is essentially identical in adults and children. Taken as a whole, this information supports a conclusion that the generally accepted therapeutic range of total carbamazepine in plasma (i.e. 4 to 12 mcg/mL) is the same in children and adults. The evidence assembled was primarily obtained from short-term use of carbamazepine. The safety of carbamazepine in children has been systematically studied up to 6 months. No longer-term data from clinical trials is available. Geriatric Use No systematic studies in geriatric patients have been conducted.

CLINICAL PHARMACOLOGY In controlled clinical trials, carbamazepine has been shown to be effective in the treatment of psychomotor and grand mal seizures, as well as trigeminal neuralgia. Mechanism of Action Carbamazepine has demonstrated anticonvulsant properties in rats and mice with electrically and chemically induced seizures. It appears to act by reducing polysynaptic responses and blocking the post-tetanic potentiation. Carbamazepine greatly reduces or abolishes pain induced by stimulation of the infraorbital nerve in cats and rats. It depresses thalamic potential and bulbar and polysynaptic reflexes, including the linguomandibular reflex in cats. Carbamazepine is chemically unrelated to other anticonvulsants or other drugs used to control the pain of trigeminal neuralgia. The mechanism of action remains unknown. The principal metabolite of carbamazepine, carbamazepine-10, 11-epoxide, has anticonvulsant activity as demonstrated in several in vivo animal models of seizures. Though clinical activity for the epoxide has been postulated, the significance of its activity with respect to the safety and efficacy of carbamazepine has not been established. Pharmacokinetics In clinical studies, Carbamazepine suspension, conventional tablets, and XR tablets delivered equivalent amounts of drug to the systemic circulation. However, the suspension was absorbed somewhat faster, and the XR tablet slightly slower, than the conventional tablet. The bioavailability of the XR tablet was 89% compared to suspension. Following a twice a day dosage regimen, the suspension provides higher peak levels and lower trough levels than those obtained from the conventional tablet for the same dosage regimen. On the other hand, following a three times a day dosage regimen, Carbamazepine suspension affords steady-state plasma levels comparable to Carbamazepine tablets given twice a day when administered at the same total mg daily dose. Following a twice a day dosage regimen, Carbamazepine-XR tablets afford steady-state plasma levels comparable to conventional Carbamazepine tablets given four times a day, when administered at the same total mg daily dose.Carbamazepine in blood is 76% bound to plasma proteins. Plasma levels of Carbamazepine are variable and may range from 0.5 to 25 mcg/mL, with no apparent relationship to the daily intake of the drug. Usual adult therapeutic levels are between 4 and 12 mcg/mL. In polytherapy, the concentration of Carbamazepine and concomitant drugs may be increased or decreased during therapy, and drug effects may be altered (see PRECAUTIONS , Drug Interactions ). Following chronic oral administration of suspension, plasma levels peak at approximately 1.5 hours compared to 4 to 5 hours after administration of conventional Carbamazepine tablets, and 3 to 12 hours after administration of Carbamazepine-XR tablets. The CSF/serum ratio is 0.22, similar to the 24% unbound Carbamazepine in serum. Because Carbamazepine induces its own metabolism, the half-life is also variable. Autoinduction is completed after 3 to 5 weeks of a fixed dosing regimen. Initial half-life values range from 25 to 65 hours, decreasing to 12 to 17 hours on repeated doses. Carbamazepine is metabolized in the liver. Cytochrome P450 3A4 was identified as the major isoform responsible for the formation of carbamazepine-10,11-epoxide from Carbamazepine. Human microsomal epoxide hydrolase has been identified as the enzyme responsible for the formation of the 10,11-transdiol derivative from carbamazepine10,11 epoxide. After oral administration of 14 C-carbamazepine, 72% of the administered radioactivity was found in the urine and 28% in the feces. This urinary radioactivity was composed largely of hydroxylated and conjugated metabolites, with only 3% of unchanged Carbamazepine. The pharmacokinetic parameters of carbamazepine disposition are similar in children and in adults. However, there is a poor correlation between plasma concentrations of carbamazepine and Carbamazepine Tablets dose in children. Carbamazepine is more rapidly metabolized to carbamazepine-10, 11-epoxide (a metabolite shown to be equipotent to carbamazepine as an anticonvulsant in animal screens) in the younger age groups than in adults. In children below the age of 15, there is an inverse relationship between CBZ-E/CBZ ratio and increasing age (in one report from 0.44 in children below the age of 1 year to 0.18 in children between 10 to 15 years of age). The effects of race and gender on carbamazepine pharmacokinetics have not been systematically evaluated.

Mechanism of Action Carbamazepine has demonstrated anticonvulsant properties in rats and mice with electrically and chemically induced seizures. It appears to act by reducing polysynaptic responses and blocking the post-tetanic potentiation. Carbamazepine greatly reduces or abolishes pain induced by stimulation of the infraorbital nerve in cats and rats. It depresses thalamic potential and bulbar and polysynaptic reflexes, including the linguomandibular reflex in cats. Carbamazepine is chemically unrelated to other anticonvulsants or other drugs used to control the pain of trigeminal neuralgia. The mechanism of action remains unknown. The principal metabolite of carbamazepine, carbamazepine-10, 11-epoxide, has anticonvulsant activity as demonstrated in several in vivo animal models of seizures. Though clinical activity for the epoxide has been postulated, the significance of its activity with respect to the safety and efficacy of carbamazepine has not been established.

Pharmacokinetics In clinical studies, Carbamazepine suspension, conventional tablets, and XR tablets delivered equivalent amounts of drug to the systemic circulation. However, the suspension was absorbed somewhat faster, and the XR tablet slightly slower, than the conventional tablet. The bioavailability of the XR tablet was 89% compared to suspension. Following a twice a day dosage regimen, the suspension provides higher peak levels and lower trough levels than those obtained from the conventional tablet for the same dosage regimen. On the other hand, following a three times a day dosage regimen, Carbamazepine suspension affords steady-state plasma levels comparable to Carbamazepine tablets given twice a day when administered at the same total mg daily dose. Following a twice a day dosage regimen, Carbamazepine-XR tablets afford steady-state plasma levels comparable to conventional Carbamazepine tablets given four times a day, when administered at the same total mg daily dose.Carbamazepine in blood is 76% bound to plasma proteins. Plasma levels of Carbamazepine are variable and may range from 0.5 to 25 mcg/mL, with no apparent relationship to the daily intake of the drug. Usual adult therapeutic levels are between 4 and 12 mcg/mL. In polytherapy, the concentration of Carbamazepine and concomitant drugs may be increased or decreased during therapy, and drug effects may be altered (see PRECAUTIONS , Drug Interactions ). Following chronic oral administration of suspension, plasma levels peak at approximately 1.5 hours compared to 4 to 5 hours after administration of conventional Carbamazepine tablets, and 3 to 12 hours after administration of Carbamazepine-XR tablets. The CSF/serum ratio is 0.22, similar to the 24% unbound Carbamazepine in serum. Because Carbamazepine induces its own metabolism, the half-life is also variable. Autoinduction is completed after 3 to 5 weeks of a fixed dosing regimen. Initial half-life values range from 25 to 65 hours, decreasing to 12 to 17 hours on repeated doses. Carbamazepine is metabolized in the liver. Cytochrome P450 3A4 was identified as the major isoform responsible for the formation of carbamazepine-10,11-epoxide from Carbamazepine. Human microsomal epoxide hydrolase has been identified as the enzyme responsible for the formation of the 10,11-transdiol derivative from carbamazepine10,11 epoxide. After oral administration of 14 C-carbamazepine, 72% of the administered radioactivity was found in the urine and 28% in the feces. This urinary radioactivity was composed largely of hydroxylated and conjugated metabolites, with only 3% of unchanged Carbamazepine. The pharmacokinetic parameters of carbamazepine disposition are similar in children and in adults. However, there is a poor correlation between plasma concentrations of carbamazepine and Carbamazepine Tablets dose in children. Carbamazepine is more rapidly metabolized to carbamazepine-10, 11-epoxide (a metabolite shown to be equipotent to carbamazepine as an anticonvulsant in animal screens) in the younger age groups than in adults. In children below the age of 15, there is an inverse relationship between CBZ-E/CBZ ratio and increasing age (in one report from 0.44 in children below the age of 1 year to 0.18 in children between 10 to 15 years of age). The effects of race and gender on carbamazepine pharmacokinetics have not been systematically evaluated.

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Before prescribing carbamazepine, the physician should be thoroughly familiar with the details of this prescribing information, particularly regarding use with other drugs, especially those which accentuate toxicity potential.

Carbamazepine Carbamazepine STARCH, CORN CROSCARMELLOSE SODIUM FD&C RED NO. 40 SILICON DIOXIDE MAGNESIUM STEARATE CARBAMAZEPINE CARBAMAZEPINE Capsule shaped biconvex CAR;200

ANDA207798

Carbamazepine

Carbamazepine

50090-5740

HUMAN PRESCRIPTION DRUG

ORAL

CARBAMAZEPINE Label Image

MEDICATION GUIDE CARBAMAZEPINE (kar-bah-MAZ-eh-peen) TABLETS USP, 100 mg and 200 mg Read this Medication Guide before you start taking carbamazepine. There may be new information. This information does not take the place of talking to your healthcare provider about your medical condition or treatment. What is the most important information I should know about carbamazepine? Do not stop taking carbamazepine without first talking to your healthcare provider. Stopping carbamazepine suddenly can cause serious problems. Carbamazepine can cause serious side effects, including : 1. Carbamazepine may cause rare but serious skin rashes that may lead to death. These serious skin reactions are more likely to happen when you begin taking carbamazepine within the first four months of treatment but may occur at later times. These reactions can happen in anyone, but are more likely in people of Asian descent. If you are of Asian descent, you may need a genetic blood test before you take carbamazepine to see if you are at a higher risk for serious skin reactions with this medicine. Symptoms may include: • skin rash • hives • sores in your mouth • blistering or peeling of the skin 2. Carbamazepine may cause rare but serious blood problems. Symptoms may include: • fever, sore throat, or other infections that come and go or do not go away • easy bruising • red or purple spots on your body • bleeding gums or nose bleeds • severe fatigue or weakness 3. Carbamazepine may cause allergic reactions or serious problems, which may affect organs and other parts of your body like the liver or blood cells. You may or may not have a rash with these types of reactions. Call your healthcare provider right away if you have any of the following: • swelling of your face, eyes, lips, or tongue • a skin rash • painful sores in the mouth or around your eyes • unusual bruising or bleeding • frequent infections or infections that do not go away • fever, swollen glands, or sore throat that do not go away or come and go • trouble swallowing or breathing • hives • yellowing of your skin or eyes • severe fatigue or weakness • an extreme increase in activity and talking (mania) • severe muscle pain 4. Like other antiepileptic drugs, carbamazepine may cause suicidal thoughts or actions in a very small number of people, about 1 in 500. Call your healthcare provider right away if you have any of these symptoms, especially if they are new, worse, or worry you: • thoughts about suicide or dying • attempts to commit suicide • new or worse depression • new or worse anxiety • feeling agitated or restless • panic attacks • trouble sleeping (insomnia) • new or worse irritability • acting aggressive, being angry, or violent • acting on dangerous impulses • an extreme increase in activity and talking (mania) • other unusual changes in behavior or mood How can I watch for early symptoms of suicidal thoughts and actions? • Pay attention to any changes, especially sudden changes, in mood, behaviors, thoughts, or feelings. • Keep all follow-up visits with your healthcare provider as scheduled. Call your healthcare provider between visits as needed, especially if you are worried about symptoms. Do not stop carbamazepine without first talking to a healthcare provider. Stopping carbamazepine suddenly can cause serious problems. You should talk to your healthcare provider before stopping. Suicidal thoughts or actions can be caused by things other than medicines. If you have suicidal thoughts or actions, your healthcare provider may check for other causes. What is carbamazepine? Carbamazepine is a prescription medicine used to treat: • certain types of seizures (partial, tonic-clonic, mixed) • certain types of nerve pain (trigeminal and glossopharyngeal neuralgia) Carbamazepine is not a regular pain medicine and should not be used for aches or pains. Who should not take carbamazepine? Do not take carbamazepine if you: • have a history of bone marrow depression. • are allergic to carbamazepine or any of the ingredients in Carbamazepine Tablets. See the end of this Medication Guide for a complete list of ingredients in Carbamazepine Tablets. • take nefazodone. • are allergic to medicines called tricyclic antidepressants (TCAs). Ask your healthcare provider or pharmacist for a list of these medicines if you are not sure. • have taken a medicine called a Monoamine Oxidase Inhibitor (MAOI) in the last 14 days. Ask your healthcare provider or pharmacist for a list of these medicines if you are not sure. What should I tell my healthcare provider before taking carbamazepine? Before you take carbamazepine, tell your healthcare provider if you: • have or have had suicidal thoughts or actions, depression, or mood problems • have or ever had heart problems • have or ever had blood problems • have or ever had liver problems • have or ever had kidney problems • have or ever had allergic reactions to medicines • have or ever had increased pressure in your eye • have any other medical conditions • drink grapefruit juice or eat grapefruit • use birth control. Carbamazepine may make your birth control less effective. Tell your healthcare provider if your menstrual bleeding changes while you take birth control and carbamazepine. • are pregnant or plan to become pregnant. Carbamazepine may harm your unborn baby. Tell your healthcare provider right away if you become pregnant while taking carbamazepine. You and your healthcare provider should decide if you should take carbamazepine while you are pregnant. ▪ If you become pregnant while taking carbamazepine, talk to your healthcare provider about registering with the North American Antiepileptic Drug (NAAED) Pregnancy Registry. The purpose of this registry is to collect information about the safety of antiepileptic medicine during pregnancy. You can enroll in this registry by calling 1-888-233-2334. • are breastfeeding or plan to breastfeed. Carbamazepine passes into breast milk. You and your healthcare provider should discuss whether you should take carbamazepine or breastfeed; you should not do both. Tell your healthcare provider about all the medicines you take , including prescription and non-prescription medicines, vitamins, and herbal supplements. Taking carbamazepine with certain other medicines may cause side effects or affect how well they work. Do not start or stop other medicines without talking to your healthcare provider. Know the medicines you take. Keep a list of them and show it to your healthcare provider and pharmacist when you get a new medicine. How should I take carbamazepine? • Do not stop taking carbamazepine without first talking to your healthcare provider. Stopping carbamazepine suddenly can cause serious problems. Stopping seizure medicine suddenly in a patient who has epilepsy may cause seizures that will not stop (status epilepticus). • Take carbamazepine exactly as prescribed. Your healthcare provider will tell you how much carbamazepine to take. • Your healthcare provider may change your dose. Do not change your dose of carbamazepine without talking to your healthcare provider. • Take carbamazepine with food. • If you take too much carbamazepine , call your healthcare provider or local Poison Control Center right away. What should I avoid while taking carbamazepine ? • Do not drink alcohol or take other drugs that make you sleepy or dizzy while taking carbamazepine until you talk to your healthcare provider. Carbamazepine taken with alcohol or drugs that cause sleepiness or dizziness may make your sleepiness or dizziness worse. • Do not drive, operate heavy machinery, or do other dangerous activities until you know how carbamazepine affects you. Carbamazepine may slow your thinking and motor skills. What are the possible side effects of carbamazepine ? See "What is the most important information I should know about carbamazepine ?" Carbamazepine may cause other serious side effects. These include: • Irregular heartbeat - symptoms include: o Fast, slow, or pounding heartbeat o Shortness of breath o Feeling lightheaded o Fainting • Liver problem-symptoms include: o yellowing of your skin or the whites of your eyes o dark urine o pain on the right side of your stomach area (abdominal pain) o easy bruising o loss of appetite o nausea or vomiting Get medical help right away if you have any of the symptoms listed above or listed in "What is the most important information I should know about carbamazepine ?" The most common side effects of carbamazepine include: • dizziness • drowsiness • problems with walking and coordination (unsteadiness) • nausea • vomiting These are not all the possible side effects of carbamazepine . For more information, ask your healthcare provider or pharmacist. Tell your healthcare provider if you have any side effect that bothers you or that does not go away. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA­-1088. How should I store Carbamazepine Tablets? • Store Carbamazepine Tablets at 20° to 25°C (68° to 77°F); excursions permitted between 15° to 30°C (59° to 86°F) [See USP Controlled Room Temperature]. • Do not store Carbamazepine Tablets above 30°C (86°F) • Keep Carbamazepine Tablets dry. Keep Carbamazepine Tablets and all medicines out of the reach of children. General Information about Carbamazepine Medicines are sometimes prescribed for purposes other than those listed in a Medication Guide. Do not use carbamazepine for a condition for which it was not prescribed. Do not give carbamazepine to other people, even if they have the same symptoms that you have. It may harm them. This Medication Guide summarizes the most important information about carbamazepine . If you would like more information, talk with your healthcare provider. You can ask your pharmacist or healthcare provider for the full prescribing information about carbamazepine that is written for health professionals. PHARMACIST: Umedica Laboratories Pvt. Ltd. intent to provide a sufficient quantity of medication guide with each bottle such that the pharmacist may provide one with each prescription that is dispensed. What are the ingredients in Carbamazepine Tablets ? Active ingredient: carbamazepine, USP Inactive ingredients: • Carbamazepine Tablets : pregelatinized maize starch, FD & C red 40, croscarmellose sodium, colloidal silicon dioxide and magnesium stearate. This Medication Guide has been approved by the U.S Food and Drug Administration. Manufactured by: Umedica Laboratories Pvt. Ltd. Plot No. 221 and 221/1, GIDC, IInd Phase, Vapi, Gujarat 396195, INDIA (IND). Manufactured for: Nivagen Pharmaceuticals, Inc. Sacramento, CA 95827, USA Toll free number: 1-877-977-0687 Revised: May 2023, V-06

HOW SUPPLIED Product: 50090-5740 NDC: 50090-5740-0 100 TABLET in a BOTTLE NDC: 50090-5740-3 28 TABLET in a BOTTLE

WARNINGS SERIOUS DERMATOLOGIC REACTIONS AND HLA-B*1502 ALLELE SERIOUS AND SOMETIMES FATAL DERMATOLOGIC REACTIONS, INCLUDING TOXIC EPIDERMAL NECROLYSIS (TEN) AND STEVENS-JOHNSON SYNDROME (SJS), HAVE BEEN REPORTED DURING TREATMENT WITH CARBAMAZEPINE. THESE REACTIONS ARE ESTIMATED TO OCCUR IN 1 TO 6 PER 10,000 NEW USERS IN COUNTRIES WITH MAINLY CAUCASIAN POPULATIONS, BUT THE RISK IN SOME ASIAN COUNTRIES IS ESTIMATED TO BE ABOUT 10 TIMES HIGHER. STUDIES IN PATIENTS OF CHINESE ANCESTRY HAVE FOUND A STRONG ASSOCIATION BETWEEN THE RISK OF DEVELOPING SJS/TEN AND THE PRESENCE OF HLA-B*1502, AN INHERITED ALLELIC VARIANT OF THE HLA-B GENE. HLA-B*1502 IS FOUND ALMOST EXCLUSIVELY IN PATIENTS WITH ANCESTRY ACROSS BROAD AREAS OF ASIA. PATIENTS WITH ANCESTRY IN GENETICALLY AT-RISK POPULATIONS SHOULD BE SCREENED FOR THE PRESENCE OF HLA-B*1502 PRIOR TO INITIATING TREATMENT WITH CARBAMAZEPINE. PATIENTS TESTING POSITIVE FOR THE ALLELE SHOULD NOT BE TREATED WITH CARBAMAZEPINE UNLESS THE BENEFIT CLEARLY OUTWEIGHS THE RISK (SEE WARNINGS AND PRECAUTIONS , LABORATORY TESTS). APLASTIC ANEMIA AND AGRANULOCYTOSIS APLASTIC ANEMIA AND AGRANULOCYTOSIS HAVE BEEN REPORTED IN ASSOCIATION WITH THE USE OF CARBAMAZEPINE. DATA FROM A POPULATION-BASED CASE CONTROL STUDY DEMONSTRATE THAT THE RISK OF DEVELOPING THESE REACTIONS IS 5 TO 8 TIMES GREATER THAN IN THE GENERAL POPULATION. HOWEVER, THE OVERALL RISK OF THESE REACTIONS IN THE UNTREATED GENERAL POPULATION IS LOW, APPROXIMATELY SIX PATIENTS PER ONE MILLION POPULATION PER YEAR FOR AGRANULOCYTOSIS AND TWO PATIENTS PER ONE MILLION POPULATION PER YEAR FOR APLASTIC ANEMIA. ALTHOUGH REPORTS OF TRANSIENT OR PERSISTENT DECREASED PLATELET OR WHITE BLOOD CELL COUNTS ARE NOT UNCOMMON IN ASSOCIATION WITH THE USE OF CARBAMAZEPINE, DATA ARE NOT AVAILABLE TO ESTIMATE ACCURATELY THEIR INCIDENCE OR OUTCOME. HOWEVER, THE VAST MAJORITY OF THE CASES OF LEUKOPENIA HAVE NOT PROGRESSED TO THE MORE SERIOUS CONDITIONS OF APLASTIC ANEMIA OR AGRANULOCYTOSIS. BECAUSE OF THE VERY LOW INCIDENCE OF AGRANULOCYTOSIS AND APLASTIC ANEMIA, THE VAST MAJORITY OF MINOR HEMATOLOGIC CHANGES OBSERVED IN MONITORING OF PATIENTS ON CARBAMAZEPINE ARE UNLIKELY TO SIGNAL THE OCCURRENCE OF EITHER ABNORMALITY. NONETHELESS, COMPLETE PRETREATMENT HEMATOLOGICAL TESTING SHOULD BE OBTAINED AS A BASELINE. IF A PATIENT IN THE COURSE OF TREATMENT EXHIBITS LOW OR DECREASED WHITE BLOOD CELL OR PLATELET COUNTS, THE PATIENT SHOULD BE MONITORED CLOSELY. DISCONTINUATION OF THE DRUG SHOULD BE CONSIDERED IF ANY EVIDENCE OF SIGNIFICANT BONE MARROW DEPRESSION DEVELOPS.