Vyvanse® (lisdexamfetamine)

Lisdexamfetamine (Trade name: Vyvanse®) is a stimulant medication in the amphetamine class primarily used in the treatment of attention-deficit/hyperactivity disorder (ADHD). Lisdexamfetamine is a substituted amphetamine and an inactive prodrug of dextroamphetamine.

  • Lasts 13-14 hours
  • The drug ingested is a pro-drug (inactive product) lisdexamfetamine dimesylate (i.e. - lysine is attached to lisdexamfetamine)
    • Whereas other long-acting stimulants achieve extended duration of action through “engineering,” Vyvanse achieves this through chemical conversion (hydrolysis of the covalent bond between L-lysine and d-amphetamine)
    • There is no abuse potential because of this mechanism, as first-pass metabolism is the rate-limiting step.
  • Lisdexamfetamine dimesylate is is converted in the serum to L-lysine (a naturally occurring amino acid) and pharmacologically active d-amphetamine

There are many different formulations of amphetamines. These are all clinically the same basic ingredient —- there are just different delivery mechanisms of each.

Different Formulations of Amphetamine Psychostimulants

Tradename Active ingredient Immediate/Delayed (%) Duration Formulations Starting Dose Titration Notes
Adderall XR Amphetamine mixed salts 50/50 12 hours 5, 10, 15, 20, 25, 30 mg cap 5-10 mg q AM (adults can start at 10 mg) • ↑ 5-10 mg at weekly intervals
• Maximum dose/day: Children = 30 mg
• Adolescents & Adults = 20-30 mg
• Mimics BID amphetamine dosing (one part delayed release, one part immediate release)
• It lasts longer (12 hours) than Biphentin, which mimics BID methylphenidate
• Capsules may be opened up and the beads inside sprinkled on soft foods (e.g. - apple sauce, yogurt, ice cream)
Vyvanse Lisdexamfetamine N/A 12-14 hours 10, 20, 30, 40, 50, 60, 70 mg cap 20-30 mg q AM ­• ↑­ 10-20 mg by clinical discretion at weekly intervals
• Maximum dose/day: All ages = 60 mg
• The drug ingested is lisdexamfetamine dimesylate a pro-drug
• No abuse potential because of this mechanism
• Low abuse potential
• Capsules may be opened up and the powder inside mixed into water (taste is slightly sweet), orange juice, or yogurt
Dexedrine Dextro-amphetamine 100/0 4 hours 5 mg tab 2.5-5 mg BID ­• ↑ 5 mg at weekly intervals
­• Maximum dose/day: (q.d. or b.i.d.)
­• Children & Adolescents = 20-30 mg
­• Adults = 50 mg
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Dexedrine Spansule Dextro-amphetamine 50/50 Purportedly lasts 10-12 hours, but more likely 6-8 hours 10, 15 mg cap 10mg q AM ­• ↑ 5 mg at weekly intervals
­• Maximum dose/day: (q.d. or b.i.d.)
­• Children & Adolescents = 20-30 mg
­• Adults = 50 mg
• Essentially mimics BID dexedrine tabs
• Capsule containing 2 kinds of beads (50% d-amphetamine, 50% polymer-coated d-amphetamine)
• Capsules may be opened up and the beads inside sprinkled on soft foods

Psychosis Risk

Dextroamphetamine

  • Capsules may be opened up and the powder inside (taste is slightly sweet) can be mixed into water, orange juice, or yogurt.