Are Amphetamine Salts ER and Adderall XR the Same?
Yes, extended-release mixed amphetamine salts (generic) are therapeutically equivalent to Adderall XR (brand name), containing the identical active ingredients in the same 3:1 ratio of dextroamphetamine to levoamphetamine with comparable bioavailability and pharmacokinetic profiles. 1
Active Ingredient Composition
- Both formulations contain mixed amphetamine salts in a 3:1 ratio of dextroamphetamine to levoamphetamine, ensuring identical active pharmaceutical ingredients 1
- The bioavailability and pharmacokinetic profiles of generic amphetamine salts ER are comparable to brand-name Adderall XR 1
Delivery Mechanism
- Both utilize a dual-bead delivery system with immediate-release pellets that release the first half of the dose upon ingestion and delayed-release pellets that begin releasing active drug approximately 4 hours later 1
- This two-stage delivery provides a rapid onset of action within 1.5 hours and maintains therapeutic coverage for 12 hours 1, 2
Clinical Equivalence
- Generic extended-release amphetamine salts must demonstrate bioequivalence to Adderall XR through rigorous FDA testing, including virtual bioequivalence simulations across various populations 3
- The efficacy, safety, and extended duration of action have been established through clinical studies showing identical therapeutic profiles 1
Practical Considerations
Important caveat: While therapeutically equivalent, individual patients may experience differences due to:
- Inactive ingredients (excipients) that differ between manufacturers, which can affect tolerability in sensitive individuals 3
- Manufacturing variability within FDA-approved bioequivalence ranges (typically 80-125% of reference product) 3
- Patient perception and placebo effects related to brand recognition
Regulatory Status
- Generic amphetamine salts ER are FDA-approved as AB-rated therapeutic equivalents to Adderall XR, meaning they meet stringent standards for pharmaceutical equivalence and bioequivalence 3
- Both formulations are classified as long-acting amphetamine stimulants approved for ADHD treatment 4
Bottom line: Prescribe either formulation with confidence in their therapeutic equivalence, but monitor individual patient response during any switch between manufacturers, as minor differences in inactive ingredients may occasionally affect tolerability without compromising efficacy.