What is the proper usage and dosage of amphetamine (amphetamine) for treating ADHD and narcolepsy?

Proper Usage and Dosage of Amphetamine for ADHD and Narcolepsy

For treating ADHD and narcolepsy, amphetamine should be started at 5-10 mg daily for adults with ADHD (10 mg for Adderall XR) and titrated by 5 mg weekly up to a maximum of 50-60 mg daily, while narcolepsy treatment ranges from 5-60 mg daily in divided doses. 1, 2

Dosing for ADHD

Adults with ADHD:

• Start with 10 mg once daily in the morning for amphetamine mixed salts (Adderall XR) 1
• Titrate dose by 5 mg weekly increments up to a maximum of 50 mg daily 1
• Avoid late evening doses to prevent insomnia 2

Children with ADHD:

• Not recommended for children under 3 years of age 2
• Ages 3-5: Start with 2.5 mg daily, increase by 2.5 mg weekly until optimal response 2
• Ages 6 and older: Start with 5 mg once or twice daily, increase by 5 mg weekly 2
• Maximum dose rarely needs to exceed 40 mg per day in children 1, 2

Dosing for Narcolepsy:

• Adults: Start with 10 mg daily, increase by 10 mg at weekly intervals until optimal response 2
• Children (12+ years): Start with 10 mg daily, increase by 10 mg weekly 2
• Children (6-12 years): Start with 5 mg daily, increase by 5 mg weekly 2
• Usual effective dose range: 5-60 mg per day in divided doses 2
• First dose should be given upon awakening with additional doses at 4-6 hour intervals 2

Specific Formulations

Dextroamphetamine (Dexedrine):

• Immediate release: Start with 5 mg twice daily, increase by 5 mg weekly to maximum 50 mg daily 1
• Spansule (sustained release): Start with 10 mg once daily in morning, increase by 5 mg 1

Lisdexamfetamine (Vyvanse):

• Start with 20-30 mg once daily in morning 1
• Increase by 10 mg weekly to maximum of 70 mg daily 1

Administration Guidelines

• Administer at lowest effective dosage with individual adjustment 2
• Give first dose in the morning after breakfast and around noon after lunch 1
• For immediate-release formulations, doses should be given 2-3 times daily due to short duration of action 1
• Periodic drug holidays should be considered to determine if continued therapy is needed 2
• Baseline blood pressure, pulse, height, and weight should be obtained before starting treatment 1

Monitoring and Side Effect Management

• Monitor blood pressure and pulse regularly (quarterly in adults) 1, 3
• Amphetamines increase systolic blood pressure by approximately 1.93 mmHg and diastolic by 1.84 mmHg 3
• Heart rate typically increases by about 3.71 beats per minute 3
• Systematically assess for side effects including insomnia, anorexia, headaches, social withdrawal, and tics 1
• Weight should be monitored at each visit to assess appetite suppression 1
• Follow-up appointments should be at least monthly until symptoms stabilize 1

Special Populations

Pregnancy:

• Amphetamines do not appear to be associated with major congenital malformations 1, 4
• Some studies suggest possible small increased risks for gastroschisis, preeclampsia, and preterm birth, but these associations are inconsistent across studies 1

Breastfeeding:

• Rated L3 (moderately safe) for breastfeeding 1
• Monitor breastfed infants for irritability, insomnia, and feeding difficulties 1

Common Pitfalls and Caveats

• Exceeding recommended maximum doses does not necessarily improve efficacy and may increase side effects 1
• Withdrawal from treatment due to adverse effects is 2.69 times more likely with amphetamines compared to placebo 3
• Amphetamines have high potential for abuse (DEA Schedule II controlled substances) 5
• Therapeutic use should be distinguished from non-prescribed use in persons with stimulant use disorder 1, 5
• Avoid use in patients with malignant hypertension, essential hypertension, or cardiac arrhythmias 1

By following these evidence-based dosing guidelines and monitoring protocols, clinicians can optimize the therapeutic benefits of amphetamines while minimizing potential adverse effects in patients with ADHD and narcolepsy.