Is it okay to switch from Vyvanse (lisdexamfetamine) to Adderall (amphetamine and dextroamphetamine)?

Switching from Vyvanse to Adderall for ADHD

Yes, switching from Vyvanse (lisdexamfetamine) to Adderall (mixed amphetamine salts) is appropriate and commonly done in clinical practice, as both are first-line stimulant medications for ADHD with similar mechanisms of action. 1

Rationale for Switching

Switching between ADHD stimulants is frequently indicated and represents standard practice rather than an exception. 1 Common reasons include:

• Inadequate symptom control despite appropriate dosing and duration of the current medication 1
• Unacceptable side effects such as decreased appetite, insomnia, irritability, or cardiovascular effects 1, 2
• Duration of effect mismatch with daily functional needs (Vyvanse typically lasts 13-14 hours; Adderall IR lasts 4-6 hours; Adderall XR lasts 10-12 hours) 1, 2
• Cost or insurance coverage issues, which are legitimate practical considerations in day-to-day practice 1

Pharmacologic Considerations

Both medications work through the same mechanism—they are amphetamine-based stimulants that inhibit reuptake and promote release of dopamine and norepinephrine. 1 The key difference is 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. 2, 3

Switching Strategy

Direct switch (abrupt transition) is the most practical approach for switching between these two amphetamine-based stimulants:

• Stop Vyvanse and start Adderall the next day at an equivalent dose 1
• No washout period is required because both medications have similar mechanisms and short half-lives 1
• Approximate dose conversion: 30 mg Vyvanse ≈ 10 mg Adderall; 50 mg Vyvanse ≈ 15-20 mg Adderall; 70 mg Vyvanse ≈ 20-30 mg Adderall 2, 3

Dosing Recommendations

• Adderall IR: Start with 5-10 mg once or twice daily (morning and midday), titrate in 5-10 mg increments weekly as needed 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 4
• Timing: Administer in the morning (and early afternoon for IR formulations) to minimize insomnia 1, 4

Monitoring During Transition

Monitor closely during the first 1-2 weeks for:

• Common side effects: Decreased appetite, insomnia, irritability, headache, upper abdominal pain 1, 2
• Cardiovascular effects: Blood pressure and heart rate changes 1, 4
• Symptom control: ADHD symptom improvement throughout the day 1, 2
• Rebound symptoms: Potential for symptom return in afternoon/evening, particularly with shorter-acting formulations 1

Important Caveats

• Both are Schedule II controlled substances with abuse potential, though Vyvanse's prodrug formulation theoretically confers lower abuse liability 2, 3
• Avoid in patients with: Uncontrolled hypertension, coronary artery disease, tachyarrhythmias, or active substance use disorders 1
• Consider methylphenidate-based medications (Ritalin, Concerta) as alternatives if amphetamine side effects are problematic, as they have different mechanisms and side effect profiles 1, 5
• Dose adjustments are the rule, not the exception in ADHD management—expect to titrate based on response and tolerability 1