Dosing and uses of Desoxyn (methamphetamine)
Adult dosage forms and strengths
tablet: Schedule II
- 5mg
Attention Deficit Hyperactivity Disorder
Initial: 5 mg PO qDay or q12hr; may increase daily dose at weekly intervals of 5 mg/day until optimal response
Maintenance: Usual effective dose is 20-25 mg/day; daily dose may be divided q12hr
Obesity, Short Term Treatment
5 mg PO q8hr, 30 minutes before each meaL
Pediatric dosage forms and strengths
tablet: Schedule II
- 5mg
Attention Deficit Hyperactivity Disorder
<6 years: Safety and efficacy not established
≥6 years: 5 mg PO qDay or q12hr, may increase daily dose at weekly intervals of 5 mg/day until optimal response (ususally 20-25 mg/day)
Daily dose may be divided q12hr
Obesity
<12 years: Safety and efficacy not established
≥12 years: As adults; 5 mg PO q8hr 30 minutes before each meaL
Desoxyn (methamphetamine) adverse (side) effects
Frequency not defined
Common
- Hypertension, palpitations, tachyarrhythmia
- Dizziness, drug tolerance, dysphoric mood, euphoria, headache, insomnia, restlessness, tremor
- Urticaria
- Constipation, diarrhea, taste sense altered, xerostomia
Serious
- Cardiorespiratory arrest, sudden death (rare), myocardial infarction
- Cerebrovascular accident, Gilles de la Tourette's syndrome, seizure, psychotic disorder
- Also see sympathomimetic syndrome, amphetamine toxicity
- Musculoskeletal: Rhabdomyolysis
Warnings
Black box warnings
Amphetamine has a high potential for abuse. Particular attention should be paid to the possibility of patients obtaining amphetamine for nontherapeutic use or distribution to others, and the drugs should be prescribed or dispensed sparingly
Administration of amphetamine for prolonged periods of time may lead to drug dependence and must be avoided
Use therapy in weight reduction programs when alternative therapy has been ineffective
Misuse of amphetamine may cause sudden death and serious cardiovascular adverse events
Contraindications
Within 14 days of MAOIs
Advanced arteriosclerosis
Symptomatic cardiovascular disease
Hyperthyroidism
Moderate-severe hypertension
Hypersensitivity to sympathomimetic amines
Glaucoma
Agitated state
History of drug abuse
Patients with ADHD concomitant with Tourette's syndrome
Breastfeeding
Cautions
Bipolar disorder, mild hypertension, history of seizures, diabetes (insulin requirement may be altered), history of aggressive behavior
Do not give at late evening; may cause insomnia
May impair ability to drive and/or operate heavy machinery
Alkaline urine will significantly increase half-life
Stimulants used to treat ADHD are associated with peripheral vasculopathy, including Raynaud’s phenomenon
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
High abuse potentiaL
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: do not nurse
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 Desoxyn (methamphetamine)
Mechanism of action
Amphetamine anorexigenic agent; sympathomimetic amine related to ephedrine and amphetamine with CNS stimulant activity; causes release of dopamine and other catechoamines from their storage in the presynaptic nerve terminals; inhibits monoamine transporters and oxidase, causing reuptake and metabolism of catecholamines
Pharmacokinetics
Half-Life: 4-5 hr
Absorption: Rapid
Metabolism: Liver
Excretion: Urine, varies with pH
