Benzphetamine Hydrochloride

Trade Names:Didrex- Tablets 25 mg- Tablets 50 mg

Pharmacology

Stimulates satiety center in brain, causing appetite suppression.

Indications and Usage

Short-term (few weeks) adjunct to diet plan to reduce weight.

Contraindications

Hypersensitivity to sympathomimetic amines; pregnancy; advanced arteriosclerosis; symptomatic cardiovascular disease; moderate to severe hypertension; hyperthyroidism; glaucoma; agitated states; history of drug abuse; during or within 14 days of MAOI use; coadministration with other CNS stimulants.

Dosage and Administration

PO 25 to 50 mg 1 to 3 times daily.

Storage/Stability

Store at room temperature in tightly closed, light-resistant container.

Drug Interactions

May decrease hypotensive effect.

May cause hypertensive crisis and intracranial hemorrhage.

Sympathomimetic effects of benzphetamine may be increased; increased risk of “serotonin syndrome.”

Laboratory Test Interactions

None well documented.

Adverse Reactions

Cardiovascular

Palpitations; tachycardia; arrhythmias; hypertension; hypotension; chest pain.

CNS

Hypersensitivity; dizziness; insomnia; euphoria; tremor; headache; restlessness; overstimulation; nervousness; anxiety; agitation.

Dermatologic

Urticaria; rash; erythema; hair loss.

EENT

Mydriasis; blurred vision; unpleasant taste.

GI

Dry mouth; nausea; diarrhea; constipation; stomach pain.

Genitourinary

Dysuria; urinary frequency; impotence; menstrual disturbances.

Hematologic

Bone marrow depression; agranulocytosis; leukopenia.

Miscellaneous

Excessive sweating; flushing; myalgia; gynecomastia.

Precautions

Pregnancy

Category X .

Lactation

Undetermined.

Children

Not recommended for children under 12 yr of age.

Tartrazine Sensitivity

Some products contain tartrazine, which may cause allergic-type reactions in susceptible individuals.

Drug dependency

High potential for dependence and abuse; tolerance may occur.

Overdosage

Symptoms

Restlessness, tremor, rapid respirations, tachypnea, dizziness, confusion, mood changes, panic states, dysrhythmias, palpitations, and hypertension or hypotension.

Patient Information

• Caution patient that this medication must not be taken during pregnancy or when pregnancy is possible. Advise patient to use reliable form of birth control while taking this drug.
• Remind patient to take medication on empty stomach (1 h before meal or 2 h after meal).
• Instruct patient to avoid taking medication within 6 h of bedtime because it may cause insomnia.
• Explain that anorexiant effects are temporary and tolerance to medication and dependence can occur.
• Instruct patient to notify health care provider immediately if the following symptoms occur: chest pain, palpitations, nervousness, or dizziness.
• Warn patient not to drive or perform tasks that require mental alertness if dizziness or blurred vision occurs. Notify health care provider of these disturbances.
• Tell patient to report excessive dryness of mouth, constipation, or prolonged insomnia because dosage may need to be adjusted.
• Inform patient that weight reduction requires strict adherence to dietary restrictions.

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