Lisdexamfetamine

Lisdexamfetamine

Lisdexamfetamine dimesylate (-lysine--amphetamine; sold as Vyvanse) is a psychostimulant prodrug of the phenethylamine and amphetamine chemical classes. Its molecular structure consists of dextroamphetamine coupled with the essential amino acid -lysine.

Lisdexamfetamine itself is inactive and acts as a prodrug to dextroamphetamine upon cleavage of the lysine portion of the molecule. It was developed for the intention of creating a longer-lasting and more difficult to abuse version of dextroamphetamine, as the requirement of conversion into dextroamphetamine via enzymes in the red blood cells increases its duration, regardless of the route of ingestion. The drug lisdexamfetamine dimesylate is the first prodrug of its kind. Studies conducted show that lisdexamfetamine dimesylate may have less abuse potential than d-amphetamine, and an abuse profile similar to diethylpropion at dosages that are FDA approved for treatment for ADHD, but still high abuse potential when this dosage is exceeded by over 100%. There is no increased onset or effect as occurs with IV administration of dextroamphetamine compared to oral use of the same. Intravenously administered lisdexamfetamine produced likability effects similar to placebo, therefore affirming the drug's ability to reduce abuse potential.

Lisdexamfetamine is indicated for the treatment of attention deficit hyperactivity disorder (ADHD) in children six to twelve years and in adults as an integral part of a total treatment program that may include other measures (i.e., psychological, educational, social). The safety and efficacy of lisdexamfetamine dimesylate in patients three to five years old have not been established. Important side effects of therapeutic lisdexamfetamine include stunted growth in young people and occasionally a psychosis can occur at therapeutic doses during chronic therapy as a treatment emergent side effect. When abused at high doses the risk of experiencing side effects and their severity increases.

As opposed to Adderall, which contains roughly 75% dextroamphetamine and 25% levoamphetamine, lisdexamfetamine is a single-enantiomer (dextro) amphetamine formula. This pure formulation may reduce side effects, but certain individuals exhibit a better clinical response to the mixed isomer preparation.

Vyvanse is also being investigated for possible treatment of Major Depressive Disorder, cognitive impairment associated with Schizophrenia, Excessive Daytime Sleepiness, and Binge Eating Disorder.