Dextroamphetamine Sulfate

Trade Names:Dexedrine- Tablets 5 mg

Trade Names:Dexedrine Spansules- Capsules, sustained-release 5 mg- Capsules, sustained-release 10 mg- Capsules, sustained-release 15 mg

Trade Names:Dextrostat- Tablets 5 mg

Pharmacology

Activates noradrenergic neurons causing CNS and respiratory stimulation; stimulates satiety center in brain causing appetite suppression.

Pharmacokinetics

Absorption

Well absorbed. T _max approximately 3 h (IR tablets) and approximately 8 h (SR capsules).

Distribution

Widely distributed with high concentrations in the brain.

Metabolism

Metabolized in the liver by hydroxylation, N-deakylation and deamination.

Elimination

t _½ approximately 12 h (urine pH less than 5.6, t _½ is 7 to 8 h; urine pH alkaline, t _½ is 18.6 to 33.6 h).

Indications and Usage

Treatment of narcolepsy, attention-deficit disorder with hyperactivity; adjunct therapy for short-term (ie, few weeks) exogenous obesity when alternative therapy has been ineffective.

Contraindications

Advanced arteriosclerosis; symptomatic CV disease; moderate to severe hypertension; hyperthyroidism; hypersensitivity or idiosyncratic reactions to sympathomimetic amines; glaucoma; agitated states; history of drug abuse; concurrent use or within 14 days of MAOI use.

Dosage and Administration

PO 10 mg/day; may increase weekly by 10 mg to max 60 mg/day in divided doses.

PO 5 mg/day; may increase weekly by 5 mg to max 60 mg/day in divided doses.

PO 5 mg/day; may increase weekly by 5 mg to max 40 mg/day in divided doses. Usual range is 0.1 to 0.5 mg/kg/dose every morning.

PO 2.5 mg/day; may increase weekly by 2.5 mg. Usual range is 0.1 to 0.5 mg/kg/dose every morning.

PO 5 to 10 mg 30 to 60 min before meals, up to 30 mg/day. For long-acting form, 10 to 15 mg every morning.

General Advice

• Do not crush or open sustained-release tablets.

Storage/Stability

Dispense in a tight, light-resistant container. Store at 15° to 30°C (59° to 86°F).

Drug Interactions

Amphetamines may decrease effectiveness.

Hypertensive crisis and intracranial hemorrhage may occur.

May decrease amphetamine effect.

May decrease amphetamine levels.

May increase amphetamine levels.

Laboratory Test Interactions

Plasma and urinary steroid levels may be altered.

Adverse Reactions

Cardiovascular

Palpitations; tachycardia; hypertension; arrhythmias.

CNS

Nervousness; tremors; dizziness; insomnia, euphoria; headache.

Dermatologic

Urticaria.

EENT

Dry mouth; unpleasant taste.

GI

Diarrhea; constipation; anorexia.

Genitourinary

Impotence.

Precautions

Pregnancy

Category C .

Lactation

Excreted in breast milk.

Children

Do not use as anorectic agent in children younger than 12 yr of age. Not recommended for attention-deficit disorder in children younger than 3 yr of age.

Tartrazine Sensitivity

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

Tolerance

Tolerance may occur; do not exceed recommended dose to overcome this.

Overdosage

Symptoms

Restlessness, tremor, hyperreflexia, confusion, hallucinations, panic, fatigue, depression, convulsions, coma, arrhythmias, hypertension, hypotension, circulatory collapse, nausea, vomiting, diarrhea, abdominal cramps.

Patient Information

• Instruct patient to take medication early in morning and, if possible, to take last dose at bedtime.
• Tell patient to record body weight weekly.
• Instruct patient/family to measure height monthly if patient is child.
• Tell patient to limit intake of coffee, tea, cocoa, chocolate, and caffeinated soft drinks.
• Explain importance of good oral hygiene to prevent or treat dry mouth and changes in breath odor.
• Instruct patient to be aware of increased agitation, palpitations, and dizziness, and to take precautions while performing tasks that require physical coordination or mental alertness.

Copyright © 2009 Wolters Kluwer Health.