Lisdexamfetamine is the inactive prodrug of dextroamphetamine, requiring red blood cell enzymes to cleave the lysine and activate.

Mechanism — Once activated, releases dopamine and norepinephrine via reverse transport at presynaptic neurons. The prodrug architecture produces smoother onset (60-90 min), longer duration (10-14 hours), and lower abuse liability than IR amphetamine.

Use case — ADHD, binge eating disorder. Typical 30-70 mg taken in the morning. Generally better tolerated than Adderall XR.

Caveats — Schedule II. Cardiovascular screening before initiation (heart rate, BP, family history). Appetite suppression and sleep disruption are common. Tolerance builds with chronic use — periodic drug holidays preserve response.