Dosing and uses of Dexedrine, ProCentra, Zenzedi (dextroamphetamine)
Adult dosage forms and strengths
capsule, extended-release (Dexedrine): Schedule II
- 5mg
- 10mg
- 15mg
tablet, immediate-release (Zenzedi): Schedule II
- 2.5mg
- 5mg
- 7.5mg
- 10mg
- 15mg
- 20mg
- 30mg
oral solution (ProCentra): Schedule II
- 5mg/5mL
Narcolepsy
10 mg/day PO; may titrate every week until side effects appear
Not to exceed 60 mg/day
Attention Deficit Hyperactivity Disorder
5 mg PO qDay or BID (4-6 hr apart); may increase 5 mg/day qWeek until optimal response
Rarely necessary to exceed 40 mg/day
Pediatric dosage forms and strengths
capsule, extended-release (Dexedrine): Schedule II
- 5mg
- 10mg
- 15mg
tablet, immediate-release (Zenzedi): Schedule II
- 2.5mg
- 5mg
- 7.5mg
- 10mg
- 15mg
- 20mg
- 30mg
oral solution (ProCentra): Schedule II
- 5mg/5mL
Attention Deficit Hyperactivity Disorder
<3 years: Safety and efficacy not established
3-5 years
- Initial: 2.5 mg PO qDay; may increase by 2.5 mg/day qWeek
≥6 years
- Initial: 5 mg PO qDay or BID (4-6 hr apart); may increase by 5 mg/day qWeek until optimal response
- Maintenance: 5-15 mg PO q12hr OR 5-10 mg PO q8hr
- May substitute with qDay dosing of extended-release capsules
- Rarely necessary to exceed 40 mg/day
Narcolepsy
>12 years: 10 mg PO qDay initially; may increase by 10 mg qWeek to optimal response
Geriatric dosage forms and strengths
Start at lowest dose
Narcolepsy
5 mg/day PO; may increase the dose by 5 mg/day every week until side effects appear
Not to exceed 60 mg/day
Dexedrine, ProCentra, Zenzedi (dextroamphetamine) adverse (side) effects
>10%
Appetite loss (21-22%)
Insomnia (16-20%)
Abdominal pain (11-15%)
1-10%
Vomiting
Emotional lability
Nervousness
Fatigue
Fever
Infection
Nausea
Diarrhea
Dyspepsia
Dizziness
Weight loss
Frequency not defined
Hyperactivity
Hypomania
Palpitations
Tachycardia
Hypertension
Dry mouth
Constipation
Tremor
Headache
Postmarketing reports
Musculoskeletal: Rhabdomyolysis
Warnings
Black box warnings
Dextroamphetamine has a high potential for abuse; particular attention should be paid to the possibility of patients obtaining dextroamphetamine for nontherapeutic use or distribution to others, and the drugs should be prescribed or dispensed sparingly
Administration of dextroamphetamine for prolonged periods of time may lead to drug dependence and must be avoided
Misuse of dextroamphetamine may cause sudden death and serious cardiovascular adverse events
Contraindications
Hypersensitivity
Hyperthyroidism
Glaucoma
Hypertension, advanced arteriosclerosis, symptomatic CVd
Agitated states, history of drug abuse
MAOIs: Risk of severe hypertensive reaction
Cautions
Risk of sudden death in children and adolescents with structural cardiac abnormalities; generally avoid
Risk of adverse psychiatric events; eg, hallucinations and mania
Caution in mild hypertension
Associated with peripheral vasculopathy, including Raynaud phenomenon
Difficulties with accommodation and blurring of vision have been reported with stimulant treatment
Sudden deaths, stroke, and myocardial infarction reported in adults taking stimulants at usual doses
Patients who develop symptoms such as exertional chest pain, unexplained syncope, or other symptoms suggestive of cardiac disease during stimulant treatment should undergo a prompt cardiac evaluation
Particular care should be taken in using stimulants to treat ADHD patients with comorbid bipolar disorder because of concern for possible induction of mixed/manic episode in such patients
Aggressive behavior or hostility is often observed in children and adolescents with ADHD; monitor for the appearance of or worsening of aggressive behavior or hostility
Monitor growth of children ages 7 to 10 years during treatment with stimulants; may need to interrupt therapy in patients not growing or gaining weight as expected
Stimulants may lower convulsive threshold in patients with prior history of seizure, patients with prior EEG abnormalities in absence of seizures, and very rarely, patients without a history of seizures and no prior EEG evidence of seizures; discontinue therapy in the presence of seizures
Use with caution in patients who use other sympathomimetic drugs
Amphetamines may exacerbate motor and phonic tics and Tourette’s syndrome; perform clinical evaluation for tics and Tourette’s syndrome in children and their families prior to treating with stimulant medications
Rare instances of prolonged and sometimes painful erections (priapism), sometimes requiring surgical intervention, reported with methylphenidate products; typically not reported during initiation, but often subsequent to an increase in dose; seek immediate medical attention for abnormally sustained or frequent and painful erections
Pregnancy and lactation
Pregnancy category: C
Lactation: Enters breast milk; not recommended
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Dexedrine, ProCentra, Zenzedi (dextroamphetamine)
Mechanism of action
Sympathomimetic amine that promotes release of dopamine and norepinephrine from their storage sites in the presynaptic nerve terminals; may also block reuptake of catecholamines by competitive inhibition.
Absorption
Peak plasma time: ~3 hr (immediate release); ~8 hr (sustained release)
Onset of action: 1-1.5 hr
Metabolism
Hepatic via glucuronidation and mono-oxygenase
Elimination
Half-life: 7-24 hr, dependent on urinary pH
Half-life elimination: 10-13 hr (adults)
Excretion: Urine
