I’m an adult on Vyvanse 30 mg for ADHD and want to switch to amphetamine (Adderall); should I use Adderall extended‑release (XR) or immediate‑release (IR), and what dose would be equivalent?

Switching from Vyvanse 30 mg to Adderall: Formulation and Dose Equivalence

For an adult on Vyvanse 30 mg, switch to Adderall XR 20 mg once daily in the morning, which provides comparable all-day coverage with better cost-effectiveness than immediate-release formulations. 1, 2

Why Adderall XR Over Immediate-Release

Extended-release formulations are strongly preferred over immediate-release (IR) Adderall for several critical reasons:

• Once-daily dosing with Adderall XR improves medication adherence compared to the 2–3 times daily dosing required with IR formulations, and adherence is a major predictor of treatment success 1
• XR formulations provide "around-the-clock" symptom coverage lasting approximately 10–12 hours, eliminating the rebound symptoms and mid-day dosing gaps that occur with IR products 1
• The ascending plasma concentration profile of XR formulations reduces abuse potential compared to the rapid peaks seen with IR amphetamine, making XR safer in real-world practice 1
• IR formulations require multiple daily doses (typically 5–10 mg two to three times daily), creating logistical challenges with work/school schedules and increasing the risk of missed doses 1

Dose Conversion: Vyvanse 30 mg to Adderall XR

Start with Adderall XR 20 mg once daily in the morning as the equivalent dose to Vyvanse 30 mg 1, 2:

• Vyvanse 30 mg is a prodrug that converts to approximately 8.9 mg of d-amphetamine after enzymatic hydrolysis in red blood cells 3, 4
• Adderall XR contains a 50:50 mixture of d-amphetamine and l-amphetamine salts, so 20 mg of Adderall XR provides roughly 10 mg of d-amphetamine equivalent 1
• This 20 mg starting dose accounts for the slightly higher bioavailability of Adderall's immediate component while maintaining comparable therapeutic coverage 1, 2

Titration Protocol After the Switch

• If 20 mg is insufficient after one week, increase by 5 mg weekly (to 25 mg, then 30 mg) based on symptom control and tolerability 2
• The typical therapeutic range for adults is 10–50 mg daily, with most patients achieving optimal response between 20–40 mg 1, 2
• Maximum approved dose is 50 mg daily; doses above 40 mg require clear documentation that lower doses failed and no dose-limiting side effects are present 2
• Obtain standardized ADHD rating scales weekly during titration to objectively measure symptom improvement 2

Monitoring Requirements

At baseline and each dose adjustment, measure:

• Blood pressure and pulse (both seated and standing if the patient has any orthostatic symptoms) 1, 2
• Weight and appetite changes, as amphetamines commonly suppress appetite 1, 2
• Sleep quality—administer the dose in the morning to minimize insomnia 2
• Systematic assessment of side effects including headache, irritability, and cardiovascular symptoms 2

Why Not Immediate-Release Adderall?

IR Adderall is inferior for routine ADHD management because:

• It requires 2–3 doses per day (e.g., 10 mg at 8 AM, 10 mg at noon, optional 5–10 mg at 4 PM), creating adherence problems and mid-day gaps in coverage 1
• The rapid peak and short 4–6 hour duration produce rebound symptoms (irritability, mood crashes) as each dose wears off 1
• Multiple daily doses increase the risk of diversion and misuse compared to once-daily XR formulations 1
• IR formulations are appropriate only for fine-tuning coverage (e.g., adding a small afternoon IR dose to XR if evening symptoms persist), not as primary therapy 1

Cost Considerations

• Generic Adderall XR is significantly less expensive than brand Vyvanse, making it the practical choice when cost is the primary driver for switching 1
• If insurance requires step therapy, Adderall XR typically satisfies formulary requirements as a first-line amphetamine product 1

Expected Outcomes

• Approximately 70–80% of adults achieve good symptom control when amphetamine-based stimulants are properly titrated 1
• If Adderall XR at 30–40 mg fails to control symptoms after 4 weeks, consider switching to methylphenidate (e.g., Concerta), as roughly 40% of patients respond preferentially to one stimulant class over the other 5
• Switching between stimulant families is common—41% of medication-naïve adults require a switch from their initial stimulant due to poor tolerability or inadequate response 5

Common Pitfalls to Avoid

• Do not start at 10 mg XR "to be cautious"—this dose is subtherapeutic for most adults switching from Vyvanse 30 mg and delays symptom control 2
• Do not use IR Adderall as primary therapy unless the patient has highly variable daily schedules requiring flexible dosing 1
• Do not assume treatment failure if 20 mg is insufficient—systematic titration to 30–40 mg is often necessary for optimal response 2
• Do not exceed 50 mg daily without first trying methylphenidate, as higher amphetamine doses increase cardiovascular risk without proportional benefit 2