Pharmacy Author: Omudhome Ogbru, PharmD
Medical and Pharmacy Editor: Jay W. Marks, MD

GENERIC NAME: lisdexamfetamine

BRAND NAME: Vyvanse

DRUG CLASS AND MECHANISM: Lisdexamfetamine is an oral drug used for increasing attention and decreasing impulsiveness and hyperactivity in patients with attention deficit hyperactivity disorder (ADHD). Lisdexamfetamine is a prodrug; after administration it is converted to dextroamphetamine (Adderall) in the intestines and/or liver. The dextroamphetamine, an amphetamine and stimulant for the brain, is responsible for the effect of lisdexamfetamine in ADHD. The mechanism of action of dextroamphetamine in ADHD is unknown, but scientists believe that they may stimulate the nervous system by increasing the release or reducing the inactivation of norepinephrine and dopamine in the brain. Norepinephrine and dopamine are chemicals (neurotransmitters) that nerves use for communicating with each other. The net effect of amphetamines is an increase in the effects of dopamine and norepinephrine. The FDA approved lisdexamfetamine in February 2007.

GENERIC AVAILABLE: No

PRESCRIPTION: Yes

PREPARATIONS: Capsules: 20, 30, 40, 50, 60, and 70 mg

STORAGE: Lisdexamfetamine should be stored at room temperature, 15-30 C (59-86 F), and protected from light.

PRESCRIBED FOR: Lisdexamfetamine is used for the treatment of attention deficit hyperactivity disorder (ADHD).

DOSING: The recommended dose of lisdexamfetamine for adults and pediatric patients ages (6-12) is 30 mg once daily in the morning. Doses may be increased by 10-20 mg/day at weekly intervals. The maximum dose is 70 mg daily. Lisdexamfetamine should not be administered in the afternoon because it may cause insomnia. Capsules may be swallowed whole or the contents may be dissolved in a glass of water.

DRUG INTERACTIONS: Monoamine oxidase inhibitor (MAOIs) antidepressants such as isocarboxazid (Marplan), phenelzine (Nardil), tranylcypromine (Parnate), selegiline (Eldepryl) and procarbazine (Matulane), slow the elimination of amphetamines in the body. This increases the concentration of amphetamines and their effect. This can cause serious elevations in blood pressure (hypertensive crisis) with headaches, other signs of hypertensive crisis, and even fatal reactions. Lisdexamfetamine should not be administered until 14 days after MAOIs have been discontinued in order to allow the effects of the MAOIs to dissipate.

Amphetamines increase the effect of norepinephrine. Combining both drugs may lead to serious cardiovascular toxicity.

PREGNANCY: There are no adequate studies of lisdexamfetamine in pregnant women. Amphetamines may cause premature delivery, low birth weight, and withdrawal symptoms in infants born to mothers who are dependent on amphetamines.

NURSING MOTHERS: Amphetamines are excreted in breast milk. Mothers taking amphetamines should not breast feed.

SIDE EFFECTS: Common side effects of lisdexamfetamine include upper abdominal pain, nausea, dry mouth, dizziness, weight loss, trouble sleeping, irritability, decreased appetite, and vomiting.

Lisdexamfetamine may cause blurred vision, growth retardation in children, and seizures in patients with a history of seizures. Increased blood pressure, sudden death in patients with heart problems, strokes and heart attacks have been associated with lisdexamfetamine. Patients may experience new or worsening of psychiatric symptoms (for example, manic episodes, hearing voices, hallucinations) or worsening of aggressive behavior or hostility.

Lisdexamfetamine like other amphetamines may be abused. Amphetamines have been associated with tolerance, psychological dependence, and social disability. Stopping amphetamines suddenly may cause a withdrawal syndrome that includes extreme fatigue and mental depression. Therefore, there use should be discontinued by slowly reducing the dose.