How long will a vyvanse (lisdexamfetamine) stay in your system?

Over 24 hours: Vyvanse (lisdexamfetamine) is the longest acting oral stimulant; at high enough doses, amphetamine can be detected the next day, although at fairly low concentrations. Still, like with other stimulants, it seems to be effective only on days taken. There is not evidence of which i'm aware that it accumulates over time--though it might at the highest doses.