benzphetamine hydrochloride

INDICATIONS AND USAGE Benzphetamine hydrochloride tablets, USP are indicated in the management of exogenous obesity as a short term (a few weeks) adjunct in a regimen of weight reduction based on caloric restriction in patients with an initial body mass index (BMI) of 30 kg/m2 or higher who have not responded to appropriate weight reducing regimen (diet and/or exercise) alone. Below is a chart of Body Mass Index (BMI) based on various heights and weights. BMI is calculated by taking the patient's weight, in kilograms (kg), divided by the patient's height, in meters (m), squared. Metric conversions are as follows: pounds ÷2.2 = kg; inches × 0.0254 = meters. The limited usefulness of agents of this class (See CLINICAL PHARMACOLOGY ) should be weighed against possible risks inherent in their use such as those described below. Benzphetamine hydrochloride tablets, USP are indicated for use as monotherapy only. BMI Table

DOSAGE AND ADMINISTRATION Dosage should be individualized according to the response of the patient. The suggested dosage ranges from 25 to 50 mg one to three times daily. Treatment should begin with 25 to 50 mg once daily with subsequent increase in individual dose or frequency according to response. A single daily dose is preferably given in mid-morning or mid-afternoon, according to the patient’s eating habits. In an occasional patient it may be desirable to avoid late afternoon administration. Use of benzphetamine hydrochloride is not recommended in individuals under 17 years of age.

CONTRAINDICATIONS Benzphetamine hydrochloride tablets, USP are contraindicated in patients with advanced arteriosclerosis, symptomatic cardiovascular disease, moderate to severe hypertension, hyperthyroidism, known hypersensitivity or idiosyncrasy to sympathomimetic amines, and glaucoma. Benzphetamine should not be given to patients who are in an agitated state or who have a history of drug abuse. Hypertensive crises have resulted when sympathomimetic amines have been used concomitantly or within 14 days following use of monoamine oxidase inhibitors. Benzphetamine hydrochloride tablets should not be used concomitantly with other CNS stimulants. Benzphetamine hydrochloride tablets may cause fetal harm when administered to a pregnant woman. Amphetamines have been shown to be teratogenic and embryotoxic in mammals at high multiples of the human dose. Benzphetamine hydrochloride tablets are contraindicated in women who are or may become pregnant. If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential hazard to the fetus.

ADVERSE REACTIONS The following have been associated with the use of benzphetamine hydrochloride: Cardiovascular Palpitation, tachycardia, elevation of blood pressure. There have been isolated reports of cardiomyopathy and ischemic cardiac events associated with chronic amphetamine use. Valvular heart disease associated with the use of some anorectic agents such as fenfluramine and dexfenfluramine, both independently and especially when used in combination with other anorectic drugs, have been reported. However, no cases of this valvulopathy have been reported when benzphetamine hydrochloride tablets, USP have been used alone. CNS Overstimulation, restlessness, dizziness, insomnia, tremor, sweating, headache; rarely, psychotic episodes at recommended doses; depression following withdrawal of the drug. Gastrointestinal Dryness of the mouth, unpleasant taste, nausea, diarrhea, other gastrointestinal disturbances. Allergic Urticaria and other allergic reactions involving the skin. Endocrine Changes in libido.

Cardiovascular Palpitation, tachycardia, elevation of blood pressure. There have been isolated reports of cardiomyopathy and ischemic cardiac events associated with chronic amphetamine use. Valvular heart disease associated with the use of some anorectic agents such as fenfluramine and dexfenfluramine, both independently and especially when used in combination with other anorectic drugs, have been reported. However, no cases of this valvulopathy have been reported when benzphetamine hydrochloride tablets, USP have been used alone.

CNS Overstimulation, restlessness, dizziness, insomnia, tremor, sweating, headache; rarely, psychotic episodes at recommended doses; depression following withdrawal of the drug.

Gastrointestinal Dryness of the mouth, unpleasant taste, nausea, diarrhea, other gastrointestinal disturbances.

Allergic Urticaria and other allergic reactions involving the skin.

Endocrine Changes in libido.

Drug Interactions Efficacy of benzphetamine hydrochloride tablets, USP in combination with other anorectic agents has not been studied and the combined use may have the potential for serious cardiac problems. Hypertensive crises have resulted when sympathomimetic amines have been used concomitantly or within 14 days following use of monoamine oxidase inhibitors. Benzphetamine hydrochloride tablets, USP should not be used concomitantly with other CNS stimulants. Amphetamines may decrease the hypotensive effect of antihypertensives. Amphetamines may enhance the effects of tricyclic antidepressants. Urinary alkalinizing agents increase blood levels and decrease excretion of amphetamines. Urinary acidifying agents decrease blood levels and increase excretion of amphetamines.

DESCRIPTION Benzphetamine hydrochloride tablets, USP contain the anorectic agent benzphetamine hydrochloride. Benzphetamine hydrochloride is a white crystalline powder readily soluble in water and 95% ethanol. The chemical name for benzphetamine hydrochloride, USP is d -N,α-Dimethyl-N -(phenylmethyl)-benzeneethanamine hydrochloride and its molecular weight is 275.82. The structural formula (dextro form) is represented below: Each benzphetamine hydrochloride tablet, USP for oral administration, contains 50 mg of benzphetamine hydrochloride. Inactive Ingredients: carnauba wax powder, colloidal silicon dioxide, FD&C red # 40 aluminum lake, FD&C yellow # 6 aluminum lake, lactose monohydrate, macrogol/polyethylene glycol 3350, magnesium stearate, microcrystalline cellulose 101, polyvinyl alcohol – partially hydrolyzed, sodium starch glycolate, talc and titanium dioxide. chemical structure

OVERDOSAGE Manifestations of Overdosage Acute overdosage with amphetamines may result in restlessness, tremor, tachypnea, confusion, assaultiveness and panic states. Fatigue and depression usually follow the central stimulation. Cardiovascular effects include arrhythmias, hypertension or hypotension, and circulatory collapse. Gastrointestinal symptoms include nausea, vomiting, diarrhea, and abdominal cramps. Hyperpyrexia and rhabdomyolysis have been reported and can lead to a number of associated complications. Fatal poisoning is usually preceded by convulsions and coma. Treatment of Overdosage (See WARNINGS )--- Information concerning the effects of overdosage with benzphetamine hydrochloride tablets, USP is extremely limited. The following is based on experience with other anorexiants. Management of acute amphetamine intoxication is largely symptomatic and includes sedation with a barbiturate. If hypertension is marked, the use of a nitrite or rapidly acting alpha receptor blocking agent should be considered. Experience with hemodialysis or peritoneal dialysis is inadequate to permit recommendations in this regard. Acidification of the urine increases amphetamine excretion. The oral LD 50 is 174 mg/kg in mice and 104 mg/kg in rats. The intraperitoneal LD 50 in mice is 153 mg/kg.

Manifestations of Overdosage Acute overdosage with amphetamines may result in restlessness, tremor, tachypnea, confusion, assaultiveness and panic states. Fatigue and depression usually follow the central stimulation. Cardiovascular effects include arrhythmias, hypertension or hypotension, and circulatory collapse. Gastrointestinal symptoms include nausea, vomiting, diarrhea, and abdominal cramps. Hyperpyrexia and rhabdomyolysis have been reported and can lead to a number of associated complications. Fatal poisoning is usually preceded by convulsions and coma.

Treatment of Overdosage (See WARNINGS )--- Information concerning the effects of overdosage with benzphetamine hydrochloride tablets, USP is extremely limited. The following is based on experience with other anorexiants. Management of acute amphetamine intoxication is largely symptomatic and includes sedation with a barbiturate. If hypertension is marked, the use of a nitrite or rapidly acting alpha receptor blocking agent should be considered. Experience with hemodialysis or peritoneal dialysis is inadequate to permit recommendations in this regard. Acidification of the urine increases amphetamine excretion. The oral LD 50 is 174 mg/kg in mice and 104 mg/kg in rats. The intraperitoneal LD 50 in mice is 153 mg/kg.

HOW SUPPLIED Benzphetamine hydrochloride tablets USP, 50 mg are supplied as peach, round, biconvex, film coated tablets debossed with “K” on left of the score and the number “40” debossed right of the score and plain on other side. NDC: 71335-0451-1: 30 Tablets in a BOTTLE NDC: 71335-0451-2: 7 Tablets in a BOTTLE NDC: 71335-0451-3: 14 Tablets in a BOTTLE NDC: 71335-0451-4: 21 Tablets in a BOTTLE NDC: 71335-0451-5: 42 Tablets in a BOTTLE NDC: 71335-0451-6: 84 Tablets in a BOTTLE NDC: 71335-0451-7: 60 Tablets in a BOTTLE NDC: 71335-0451-8: 90 Tablets in a BOTTLE NDC: 71335-0451-9: 120 Tablets in a BOTTLE Dispense in a tight container as defined in the USP, with a child-resistant closure (as required). Store at 20° to 25°C with excursions permitted between 15° to 30°C (59° to 86°F) [see USP Controlled Room Temperature]. Rx only Repackaged/Relabeled by: Bryant Ranch Prepack, Inc. Burbank, CA 9150