What is the difference between adderall and vyvanse (lisdexamfetamine) for add?

Delivery form: Both a amphetamine (amp). Adderall is a blend of d-amp (50%) and d, l-amp (50%). Vyvanse (lisdexamfetamine) is called a prodrug: it is d-amp linked to an amino acid. It is inactive till it gets in the body, where an enzyme cleaves the molecule, releasing d-amp. That means a very different release pattern, and it is the longest acting oral stimulant. Some like one, others the other. Both can be effective.

Delivery, duration: Think of Adderall as the active ingredient in vyvanse (lisdexamfetamine). Triple the Adderall dose to get the equivalent dose of vyvanse (lisdexamfetamine). One of the frequent problems with Adderall in my patient population was irritability that increased as dose increased; not so with vyvanse (lisdexamfetamine). Because of the attached lysine, it takes 2 hours for vyvanse (lisdexamfetamine) to start working. It lasts 12-14 hours without much " rebound" as it wears off.