Switching from Vyvanse to Adderall for ADHD

Rationale for Switching

Switching between ADHD stimulants is frequently indicated and represents standard practice rather than an exception, with common reasons including inadequate symptom control, unacceptable side effects, duration of effect mismatch, and cost or insurance coverage issues 1
Inadequate symptom control despite appropriate dosing and duration of the current medication is a reason for switching, as both Vyvanse and Adderall are first-line stimulant medications for ADHD with similar mechanisms of action 1

Both medications work through the same mechanism—they are amphetamine-based stimulants that inhibit reuptake and promote release of dopamine and norepinephrine, with the key difference being that Vyvanse is a prodrug requiring conversion to active d-amphetamine in the body, while Adderall contains a mixture of amphetamine salts (75% dextroamphetamine and 25% levoamphetamine) that are immediately active 1

Direct switch (abrupt transition) is the most practical approach for switching between these two amphetamine-based stimulants, with no washout period required because both medications have similar mechanisms and short half-lives 1
Stop Vyvanse and start Adderall the next day at an equivalent dose, with approximate dose conversion being 30 mg Vyvanse ≈ 10 mg Adderall; 50 mg Vyvanse ≈ 15-20 mg Adderall; 70 mg Vyvanse ≈ 20-30 mg Adderall 1

Adderall IR: Start with 5-10 mg once or twice daily (morning and midday), titrate in 5-10 mg increments weekly as needed, and administer in the morning (and early afternoon for IR formulations) to minimize insomnia 1
Adderall XR: Start with 10-20 mg once daily in the morning, titrate in 5-10 mg increments weekly up to maximum 50 mg daily, according to the American Academy of Child and Adolescent Psychiatry guidelines 2

Monitor closely during the first 1-2 weeks for common side effects, such as decreased appetite, insomnia, irritability, headache, upper abdominal pain, and cardiovascular effects, such as blood pressure and heart rate changes, as recommended by the American Heart Association 1, 2
Monitor for symptom control, including ADHD symptom improvement throughout the day, and rebound symptoms, such as potential for symptom return in afternoon/evening, particularly with shorter-acting formulations 1

Both are Schedule II controlled substances with abuse potential, though Vyvanse's prodrug formulation theoretically confers lower abuse liability, and should be avoided in patients with uncontrolled hypertension, coronary artery disease, tachyarrhythmias, or active substance use disorders, as stated by the National Institute of Mental Health 1
Consider methylphenidate-based medications (Ritalin, Concerta) as alternatives if amphetamine side effects are problematic, as they have different mechanisms and side effect profiles, according to the American Academy of Pediatrics 1, 3