Lisdexamfetamine for Adult ADHD: Dosage and Recommendations
For adults with ADHD, lisdexamfetamine (Vyvanse) should be initiated at 20-30 mg once daily in the morning and titrated by 10 mg weekly to a maximum of 70 mg daily. 1, 2
Dosing Protocol
- Start with 20-30 mg once daily in the morning 1
- Increase by 10 mg weekly based on response and tolerability 1, 2
- Maximum recommended dose is 70 mg daily 1, 2
- Administer in the morning to minimize insomnia 2
- Can be taken with or without food 2
Administration Options
- Swallow capsule whole 2
- Alternatively, open capsule and mix contents with yogurt, water, or orange juice and consume immediately 2
- Do not divide a single dose; take at least one full capsule daily 2
Efficacy in Adults
- Lisdexamfetamine is FDA-approved for ADHD treatment in adults 2
- Clinical trials demonstrate significant improvements in ADHD symptoms compared to placebo 3
- Amphetamine-based stimulants are considered preferred therapy for adults with ADHD 1
- Duration of action extends approximately 14 hours post-dosing in adults 4
Mechanism and Pharmacokinetics
- Lisdexamfetamine is a prodrug that is converted to dextroamphetamine after ingestion 1, 5
- Enzymatic hydrolysis occurs primarily in the blood, providing gradual release of active medication 5, 6
- The rate-limiting nature of hydrolysis provides consistent plasma concentrations throughout the day 4
- Conversion is unaffected by gastrointestinal pH and transit times 4
Safety Considerations and Monitoring
- Common adverse effects include decreased appetite, insomnia, irritability, dizziness, and weight loss 5, 3
- Monitor blood pressure and pulse regularly; recommended quarterly checks for adults 1
- Baseline physical examination including vital signs should be performed before starting treatment 1
- Assess for cardiac disease before initiating therapy 2
- Evaluate for history of tics or Tourette's syndrome prior to treatment 2
Special Populations
- For patients with severe renal impairment (GFR 15 to <30 mL/min/1.73 m²), maximum dose should not exceed 50 mg daily 2
- For end-stage renal disease (GFR <15 mL/min/1.73 m²), maximum dose is 30 mg daily 2
- Adjust dosage when using agents that alter urinary pH, as these can affect blood levels of amphetamine 2
Cautions
- High potential for abuse and misuse; assess risk throughout treatment 2
- Contraindicated in patients taking MAOIs or within 14 days of stopping MAOIs 2
- Not indicated or recommended for weight loss 2
- Avoid afternoon doses due to potential for insomnia 2
Lisdexamfetamine represents an effective treatment option for adults with ADHD, with the advantage of once-daily dosing and consistent medication levels throughout the day.