AMPHETAMINE

brands

Class

• Neuroscience-based Nomenclature: dopamine, norepinephrine reuptake inhibitor and releaser (DN-RIRe)
• Stimulant

AMPHETAMINE commonly prescribed for

(Bold for FDA approved)

How AMPHETAMINE works

• Increases norepinephrine and especially dopamine actions by blocking their reuptake and facilitating their release

• Enhancement of dopamine and norepinephrine actions in certain brain regions (e.g., dorsolateral prefrontal cortex) may improve attention, concentration, executive function, and wakefulness

• Enhancement of dopamine actions in other brain regions (e.g., basal ganglia) may improve hyperactivity

• Enhancement of dopamine and norepinephrine in yet other brain regions (e.g., medial prefrontal cortex, hypothalamus) may improve depression, fatigue, and sleepiness

How long until AMPHETAMINE works

• Some immediate effects can be seen with first dosing

• Can take several weeks to attain maximum therapeutic benefit, especially as dose is being titrated

Notable Side Effects

• Insomnia, headache, exacerbation of tics, nervousness, irritability, overstimulation, tremor, dizziness

• Anorexia, nausea, dry mouth, constipation, diarrhea, weight loss, dry mouth

• Peripheral vasculopathy, including Raynaud’s syndrome

• Can temporarily slow normal growth in children (controversial)

• Sexual dysfunction long-term (impotence, libido changes) but can also improve sexual dysfunction short-term

Life Threatening Side Effects

• Psychotic episodes, especially with parenteral abuse

• Seizures

• Palpitations, tachycardia, hypertension

• Rare activation of hypomania, mania, or suicidal ideation (controversial)

• Cardiovascular adverse effects, sudden death in patients with preexisting cardiac structural abnormalities

weight gain

unusual

sedation

unusual

What to do about AMPHETAMINE side effects

• Wait

• Adjust dose

• Switch to a long-acting stimulant

• Switch to another agent

• For insomnia, avoid dosing in afternoon/ evening

usual dosage range

• Narcolepsy: 5–60 mg/day in divided doses

• ADHD: varies by formulation; see How to Dose section

• Exogenous obesity: 30 mg/day in divided doses

Dosage Forms

• Immediate-release : 5 mg, 7.5 mg,10 mg, 12.5 mg, 15 mg, 20 mg, 30 mg

• Extended-release capsule : 5 mg, 10 mg, 15 mg, 20 mg, 25 mg, 30 mg

long term use

• Often used long-term for ADHD when ongoing monitoring documents continued efficacy

• Dependence and/or abuse may develop

• Tolerance to therapeutic effects may develop in some patients, in which case a dose increase should be considered

• Long-term stimulant use may be associated with growth suppression in children (controversial)

• Periodic monitoring of weight, blood pressure, heart rate, complete blood count, platelet counts, and liver function may be prudent

habit forming

• High abuse potential, Schedule II drug

• Patients may develop tolerance, psychological dependence

Renal Impairment

• No dose adjustment necessary

Hepatic Impairment

• No dose adjustment necessary

Cardiac Impairment

• Use with caution, particularly in patients with recent myocardial infarction or other conditions that could be negatively affected by increased blood pressure

• Do not use in patients with structural cardiac abnormalities, cardiomyopathy, serious heart arrhythmias, or coronary artery disease

Elderly

• Some patients may tolerate lower doses better

Children and Adolescents

• Safety and efficacy not established under age 3

• Use in young children should be reserved for the expert

• d,l-amphetamine may worsen symptoms of behavioral disturbance and thought disorder in psychotic children

• d,l-amphetamine has acute effects on growth hormone; long-term effects are unknown but weight and height should be monitored during long-term treatment

• ADHD: ages 3–5: initial 2.5 mg/day; can increase by 2.5 mg each week

• Narcolepsy: ages 6–12: initial 5 mg/day; increase by 5 mg each week

• Half-life and duration of clinical action tend to be shorter in younger children

• Usual dosing has been associated with sudden death in children with structural cardiac abnormalities

Pregnancy

• Controlled studies have not been conducted in pregnant women

• Infants whose mothers take d,lamphetamine during pregnancy may experience withdrawal symptoms

• Use in women of childbearing potential requires weighing potential benefits to the mother against potential risks to the fetus

• For ADHD patients, d,l-amphetamine should generally be discontinued before anticipated pregnancies

Breast Feeding

• Some drug is found in mother’s breast milk

• Recommended either to discontinue drug or formula feed

• If infant shows signs of irritability, drug may need to be discontinued