In the event of a shortage of Adderall (amphetamine and dextroamphetamine) XR 20mg, is it preferable to take 2 10mg XR capsules or switch to 20mg immediate-release (IR) formulation?

Adderall XR 20mg Shortage: Two 10mg XR Capsules vs 20mg IR

In the event of an Adderall XR 20mg shortage, take two 10mg XR capsules as a single morning dose—this maintains the same extended-release pharmacokinetics and 12-hour duration of action you need, whereas switching to 20mg IR would require multiple daily doses and fundamentally alter your medication regimen. 1, 2

Why Two 10mg XR Capsules Are Preferred

The two 10mg XR capsules deliver identical total drug content (20mg mixed amphetamine salts) with the same extended-release mechanism as a single 20mg XR capsule. 3, 4

• Each XR capsule contains immediate-release pellets that release half the dose upon ingestion and delayed-release pellets that begin releasing approximately 4 hours later 4, 5
• Taking two 10mg XR capsules simultaneously provides the same biphasic release pattern: immediate release of 10mg total (5mg from each capsule) followed by delayed release of another 10mg total approximately 4 hours later 4, 6
• The extended-release formulation maintains therapeutic coverage for 12 hours with a single morning dose 7, 4, 5
• Time to maximum concentration (Tmax) for XR formulations averages 8 hours, compared to 3 hours for immediate-release 3, 6

Why Switching to 20mg IR Is Problematic

Immediate-release Adderall requires multiple daily doses (typically twice or three times daily) to maintain symptom control throughout the day, fundamentally changing your dosing schedule and potentially causing coverage gaps. 8, 9

• IR formulations have a duration of action of only 4-6 hours, necessitating dosing after breakfast, lunch, and potentially after school 8
• A single 20mg IR dose in the morning would leave you without coverage by early afternoon 8
• Splitting to 10mg IR twice daily provides only 20mg total daily dose but with different pharmacokinetics—you'd need to take doses at specific times (after breakfast and lunch) 8, 9
• The immediate-release formulation reaches peak concentration at approximately 3 hours versus 8 hours for XR, creating a different therapeutic profile 3, 6

Practical Implementation

Simply take both 10mg XR capsules together in the morning at your usual time—no adjustment to your daily routine is needed. 1, 9

• Administer both capsules simultaneously in the morning to replicate your standard XR 20mg regimen 1, 9
• Morning administration is critical to minimize sleep disturbances 1, 9
• The bioavailability and pharmacokinetic profiles remain equivalent to your usual single 20mg XR capsule 3, 4, 10
• If you typically open your capsule and sprinkle the contents in applesauce, you can do this with both 10mg capsules—studies confirm bioequivalence between sprinkled and intact capsule administration 10

Monitoring Considerations

Continue your standard monitoring protocol without changes, as the therapeutic effect should be identical. 1, 2, 9

• No dose adjustment is needed—you're receiving the same total daily dose of 20mg 1, 2
• Monitor for the same target ADHD symptoms and side effects (insomnia, anorexia, headaches) as with your usual regimen 1, 9
• Blood pressure and pulse monitoring should continue on the same quarterly schedule for adults 2, 9
• Weight assessment at each visit remains important to detect appetite suppression 1, 9

Common Pitfall to Avoid

Do not attempt to "make up" for the shortage by taking 20mg IR once daily in the morning—this provides inadequate duration of coverage and will result in symptom breakthrough by midday. 8

• If you were to switch to IR formulation, you would need to divide the dose (typically 10mg twice daily) and coordinate timing with meals 8, 9
• This represents a fundamental change in your treatment regimen that is unnecessary when two 10mg XR capsules provide equivalent therapy 1, 4