Get Prescribed Adderall Online overnight to treat ADHD Is Adderall IR similar to Adderall XR? Adderall IR and Adderall XR belong to the same drug class group known as a stimulant. However, the primary and secondary goals of both variants are similar but also varies in some characteristics. To know about their similarities and diversities, read below- Similarities- Both activate in the drug group named as the stimulant. The primary objective of both variants is to treat ADHD. However, as a secondary treatment, both are used for narcolepsy. Adderall IR and Adderall XR function by changing some natural chemicals in the brain that contribute to hyperactivities. Diversities- Adderall IR functions immediately after consumption, whereas Adderall XR begins its mechanism steadily over time. XR properties survive in the body for up to 12 hours, but the effects of IR remain in the system for up to 6 hours. The active elements in both variants are different in amount. Both variants are available in the market with their lower subsets.