Dextroamphetamine for ADHD and Narcolepsy Treatment

Dextroamphetamine is a prescription stimulant medicine available in tablet and extended-release capsule forms. It is primarily used to treat Attention Deficit Hyperactivity Disorder (ADHD) and narcolepsy. This central nervous system stimulant works by affecting neurotransmitters to improve focus, attention, and wakefulness.

Dextroamphetamine is approved for the following uses:

• Attention Deficit Hyperactivity Disorder (ADHD): Treatment of ADHD, characterized by symptoms of hyperactivity, impulsivity, and/or inattention that cause impairment in social, academic, or occupational functioning. Diagnosis requires specific symptom criteria present before age 7 and occurring in multiple settings. Extended-release capsules are approved for patients aged 13 years and older; tablets and immediate-release formulations are indicated for pediatric patients age 3 years and above depending on formulation.
• Narcolepsy: Used to manage narcolepsy symptoms including excessive daytime sleepiness in patients aged 6 years or older depending on the formulation.

Dextroamphetamine saccharate; Amphetamine aspartate; Dextroamphetamine sulfate; Amphetamine sulfate

Dextroamphetamine belongs to the amphetamine class of central nervous system stimulants. It increases the release of neurotransmitters such as dopamine and norepinephrine in the brain, which enhances focus, attention, and alertness. The medication affects both the central and peripheral nervous systems, leading to stimulation that helps reduce symptoms of ADHD and improve wakefulness in narcolepsy.

Tablet Formulations (Immediate Release):

Dosing is individualized, starting at low doses and adjusted weekly based on response. Narcolepsy doses range from 5 to 60 mg daily in divided doses. For ADHD, pediatric dosing starts as low as 2.5-5 mg once or twice daily, adjusted weekly to optimal response, generally not exceeding 40 mg per day. Doses should be given early in the day to avoid insomnia.

Extended-Release Capsules:

Indicated for patients 13 years and older with ADHD. Administer once daily in the morning upon awakening. Starting dose is typically 12.5 mg once daily with weekly increases of 12.5 mg, not to exceed 50 mg daily in adults or 25 mg daily in adolescents. Capsules may be swallowed whole or sprinkled over applesauce and consumed immediately without chewing. Dose adjustments are recommended for patients with severe renal impairment and doses above maximums have not shown additional benefit.

Important administration notes:

• Consistency with food intake is advised, either always with or always without food.
• Do not substitute for other amphetamine products on a milligram-for-milligram basis due to differences in amphetamine base composition and pharmacokinetics.
• Late evening doses should be avoided due to risk of insomnia.
• If a dose is missed, do not take it later in the day or double the dose.

• Hypersensitivity to amphetamine or any product components.
• Concomitant use or within 14 days of monoamine oxidase inhibitors (MAOIs) including linezolid or intravenous methylene blue.
• Patients with pheochromocytoma or history thereof.

Serious Warnings and Precautions

• High abuse potential: Dextroamphetamine has a strong risk for misuse, abuse, addiction, and diversion. Monitor patients closely for signs of substance use disorder and educate about safe storage and disposal.
• Cardiac risks: Avoid use in patients with serious cardiac conditions such as structural abnormalities, cardiomyopathy, arrhythmias, or coronary artery disease due to risk of sudden death. Monitor blood pressure and heart rate regularly as stimulants can increase both.
• Psychiatric effects: May exacerbate pre-existing psychosis or induce new psychotic or manic symptoms. Screen for bipolar disorder before initiating treatment and monitor for new psychiatric symptoms.
• Pediatric growth suppression: Prolonged use in children can slow growth (height and weight). Monitor growth regularly; interrupt therapy if expected growth is not maintained.
• Seizures: May lower seizure threshold, especially in patients with a history of seizures or EEG abnormalities. Discontinue if seizures occur.
• Peripheral vasculopathy: Includes Raynaud’s phenomenon; symptoms are usually mild and intermittent but require monitoring for digital changes.
• Serotonin syndrome: Risk increased when combined with serotonergic drugs or CYP2D6 inhibitors. Discontinue treatment if symptoms occur.
• Tics and Tourette’s syndrome: May worsen or induce motor and verbal tics; assess history before use and monitor during treatment.

Common Side Effects

• Insomnia
• Loss of appetite, weight loss
• Nervousness, restlessness
• Dizziness, headache
• Increased heart rate and blood pressure
• Dry mouth
• Gastrointestinal disturbances: nausea, diarrhea, constipation
• Emotional lability

Serious but less common side effects

• Psychotic episodes (hallucinations, delusions)
• Manic episodes
• Seizures
• Peripheral vascular problems including Raynaud's phenomenon
• Cardiac complications such as tachyarrhythmia or cardiomyopathy (rare)
• Allergic reactions including angioedema and anaphylaxis
• Rhabdomyolysis (muscle breakdown)

Significant Drug Interactions

• Monoamine oxidase inhibitors (MAOIs): Contraindicated within 14 days of MAOI use due to risk of hypertensive crisis.
• Serotonergic drugs: Increased risk of serotonin syndrome when combined with SSRIs, SNRIs, triptans, tricyclic antidepressants, fentanyl, lithium, tramadol, others.
• CYP2D6 inhibitors: Can increase dextroamphetamine exposure and serotonin syndrome risk; dose modification and monitoring advised.
• Acidifying agents (ascorbic acid, fruit juices): Lower blood levels and efficacy; dose adjustments may be necessary.
• Alkalinizing agents (sodium bicarbonate): Increase blood levels and effects; co-administration should be avoided.
• Adrenergic blockers: Amphetamines may inhibit their activity.
• Tricyclic antidepressants: May potentiate cardiovascular effects; monitor and adjust therapy accordingly.
• Antihistamines: Amphetamines may counteract sedative effects.
• Antihypertensives: Amphetamines may antagonize hypotensive effects.
• Chlorpromazine, haloperidol: Inhibit stimulant effects and can be used to treat intoxication.
• Meperidine: Amphetamines potentiate analgesic effect.