Lisdexamfetamine Dimesylate

Pronunciation: lis-DEX-am-FET-a-meen dye-MES-i-late
Class: CNS stimulant/Amphetamine

Trade Names

Vyvanse
- Capsules, oral 20 mg
- Capsules, oral 30 mg
- Capsules, oral 40 mg
- Capsules, oral 50 mg
- Capsules, oral 60 mg
- Capsules, oral 70 mg

Pharmacology

Prodrug for dextroamphetamine, which is thought to block the reuptake of norepinephrine and dopamine into presynaptic neurons and to increase the release of these monoamines into the extraneuronal space.

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Pharmacokinetics

Absorption

Rapidly absorbed from the GI tract. T _max of lisdexamfetamine is 1 h. T _max of dextroamphetamine is 3.5 h. Food prolongs the T _max of dextroamphetamine by approximately 1 h (from 3.8 h at fasted state to 4.7 h after a high-fat meal).

Metabolism

Converted to dextroamphetamine and L-lysine by first-pass intestinal and/or hepatic metabolism.

Elimination

Approximately 96% of the oral dose is recovered in the urine, with 42% related to amphetamine, 25% to hippuric acid, and 2% to intact lisdexamfetamine. Plasma half-life of lisdexamfetamine is less than 1 h.

Special Populations

Elderly

Has not been studied in elderly patients.

Children

The pharmacokinetics are similar in healthy patients from 6 y of age to adult. Any differences in kinetics seen after oral administration are a result of differences in mg/kg dosing.

Gender

Systemic exposure is similar for men and women.

Race

Pharmacokinetic studies have not been conducted.

Indications and Usage

Treatment of attention deficit hyperactivity disorder (ADHD).

Contraindications

Advanced arteriosclerosis; agitated states; concomitant MAOI use or use within 14 days; glaucoma; history of drug abuse; hyperthyroidism; known hypersensitivity or idiosyncrasy to sympathomimetic amines; moderate to severe hypertension; symptomatic CV disease.

Dosage and Administration

Adults and Children 6 y and older

PO Start with 30 mg once daily in the morning. Dosage may be adjusted in 10 or 20 mg/day increments at approximately weekly intervals (max, 70 mg/day).

General Advice

• Patients should take in the morning to avoid potential insomnia.
• May be taken without regard to food.
• Capsules may be taken whole, or opened and the entire contents dissolved in a glass of water and taken immediately; do not store mixture for use at later time.
• Patient should not take less than 1 capsule daily.
• Interrupt therapy occasionally to determine if there is recurrence of behavioral symptoms sufficient to require continued therapy.

Storage/Stability

Store between 59° and 86°F.

Drug Interactions

Adrenergic blockers (eg, prazosin, propranolol)

Effects may be inhibited by amphetamines. Monitor BP and adjust the adrenergic blocker dose as needed.

Antihistamines (eg, diphenhydramine)

Sedative effects may be decreased by amphetamines. Monitor the patient and adjust treatment as needed. Because the antihistamine may be available over the counter, advise patients of the potential interaction.

Antihypertensives (eg, atenolol), veratrum alkaloids

Hypotensive effect may be antagonized by amphetamines. Monitor BP and adjust treatment as needed.

Ethosuximide

Intestinal absorption may be delayed by amphetamines. Monitor patient response and adjust treatment as needed.

Furazolidone

Risk of hypertension may be increased. Avoid coadministration.

Haloperidol, phenothiazines (eg, chlorpromazine, thioridazine)

Central stimulant effects of amphetamines may be inhibited. Use with caution. Closely monitor patient response. Do not use amphetamines for weight reduction in patients receiving phenothiazines. Chlorpromazine can be used to treat amphetamine poisoning.

Iobenguane

Lisdexamfetamine may reduce retention and diagnostic efficacy of iobenguane. False-negative iobenguane imaging tests may result. Discontinue lisdexamfetamine at least 5 biological half-lives (approximately 72 h) prior to iobenguane administration.

Lithium

Anorectic and stimulatory effects of amphetamines may be inhibited. Monitor patient response and adjust treatment as needed.

MAOIs (eg, phenelzine)

Increased risk of hypertensive crisis, malignant hyperpyrexia, and death; coadministration of MAOIs and amphetamines is contraindicated during or within 14 days following the administration of MAOIs.

Meperidine

Analgesic effect of meperidine may be potentiated. Monitor patient response and for adverse reactions, including respiratory depression. Adjust the meperidine dose as needed.

Methenamine, urinary acidifying agents (eg, ammonium chloride)

Enhanced urinary excretion of amphetamines, decreasing the efficacy. Monitor patient response and adjust the lisdexamfetamine dose as needed.

Norepinephrine

Adrenergic effect may be enhanced by amphetamine. Monitor patient response. Norepinephrine dosage adjustment may be needed.

Phenobarbital, phenytoin

Absorption may be delayed by amphetamines; synergistic anticonvulsant activity may occur. Monitor patient response and adjust therapy as needed.

Propoxyphene

Amphetamine CNS stimulation may be potentiated, increasing the risk of fatal seizures.

SSRIs (eg, fluoxetine)

Increased risk of serotonin syndrome. Monitor for CNS effects and adjust therapy as needed. Serotonin syndrome requires immediate medical attention, including withdrawal of the serotonergic agent and supportive care.

Sympathomimetics (eg, pseudoephedrine)

Amphetamines may enhance the activity of sympathomimetics. Monitor patient response and adjust therapy as needed.

Tricyclic antidepressants (eg, desipramine)

Activity may be enhanced by amphetamines; d-amphetamine brain concentrations may be increased and sustained; CV effects may be potentiated. If coadministration cannot be avoided, closely monitor the patient response and adjust treatment as needed.

Urinary alkalinizers (eg, acetazolamide, sodium bicarbonate)

Decreased urinary excretion of amphetamines, prolonging the effects and possible toxicity of amphetamines. If coadministration cannot be avoided, monitor the clinical response and adjust the lisdexamfetamine dose as needed. Avoid urinary alkalinizers in patients who took a lisdexamfetamine overdose.

Laboratory Test Interactions

Interference with urinary steroid determinations.

Adverse Reactions

Cardiovascular

Increased BP (3%); increased heart rate (2%); palpitation (postmarketing).

CNS

Insomnia (27%); irritability (10%); anxiety (6%); dizziness (5%); feeling jittery (4%); affect lability, agitation, restlessness (3%); somnolence, tic, tremor (2%); aggression, depression, dyskinesia, dysphoria, euphoria, fatigue, hallucination, logorrhea, mania, psychotic episodes, seizure, somnolence (postmarketing).

Dermatologic

Hyperhidrosis, rash (3%); Stevens-Johnson syndrome, urticaria (postmarketing).

EENT

Diplopia, mydriasis, vision blurred (postmarketing).

GI

Dry mouth (26%); upper abdominal pain (12%); vomiting (9%); diarrhea, nausea (7%).

Genitourinary

Decreased libido, erectile dysfunction (less than 2%).

Hypersensitivity

Anaphylactic reaction, angioedema, hypersensitivity (postmarketing).

Metabolic-Nutritional

Decreased appetite (39%); decreased weight (9%); anorexia (5%).

Respiratory

Dyspnea (2%).

Miscellaneous

Pyrexia (2%); eosinophilic hepatitis (postmarketing).

Precautions

Warnings Potential for abuse Amphetamines have a high potential for abuse. Administration of amphetamines for prolonged periods of time may lead to drug dependence. Pay particular attention to the possibility of patients obtaining amphetamines for nontherapeutic use or distribution to others; prescribe or dispense amphetamines sparingly. Misuse of amphetamines may cause sudden death and serious CV adverse reactions.

Monitor Monitor heart rate and BP. Monitor for the appearance or worsening of aggressive behavior or hostility. Monitor growth during treatment.

Pregnancy

Category C .

Lactation

Excreted in breast milk. Women should not breast-feed.

Children

Safety and efficacy not established in children younger than 6 y. Consistently treated children have a temporary slowing in growth rate without evidence of growth rebound.

Elderly

Per the Beers list, amphetamines have the potential for causing dependence, hypotension, angina, MI, and CNS-stimulant adverse reactions.

Aggression

Aggressive behavior and hostility have been associated with treatment in children and adolescents.

Bipolar illness

Use with caution because of possible induction of mixed/manic episodes.

CV events

Sudden death has been reported in association with CNS stimulant treatment at usual doses in children and adolescents with structural cardiac abnormalities or other serious heart problems. Sudden death, stroke, and MI have occurred in adults taking stimulant drugs in ADHD doses. Do not use stimulant products in patients with known serious structural cardiac abnormalities, cardiomyopathy, serious heart rhythm abnormalities, or other serious cardiac problems.

Dependence

Amphetamines have a high potential for dependence and abuse.

Hypertension and heart rate

Increases in BP and heart rate may occur. Use with caution in treating patients whose underlying medical conditions might be compromised by increases in BP or heart rate (eg, those with preexisting hypertension, heart failure, recent MI, ventricular arrhythmia).

Manic or psychotic symptoms

Treatment-emergent manic or psychotic symptoms (eg, delusional thinking) may occur.

Prescribing

To minimize the possibility of an overdose, prescribe the least amount feasible.

Psychosis

Symptoms of behavioral disturbance and thought disorders in patients with preexisting psychotic disorders may be exacerbated.

Seizures

The seizure threshold may be lowered in patients with a history of seizures.

Tics

Motor and phonic tics, as well as Tourette syndrome, may be exacerbated.

Tolerance

Because tolerance can occur, do not exceed the recommended dose.

Visual disturbances

Difficulties in accommodation and blurred vision have been reported with stimulant treatment.

Overdosage

Symptoms

Abdominal cramps, arrhythmias, assaultiveness, circulatory collapse, confusion, depression, diarrhea, fatigue, hallucinations, hyperpyrexia, hyperreflexia, hypertension, hypotension, nausea, panic states, rapid respiration, restlessness, rhabdomyolysis, seizures and coma, tremor, vomiting.

Patient Information

• Advise patient to read the Medication Guide before using the product for the first time and with each refill.
• Advise patients that lisdexamfetamine is a federally controlled substance because it can be abused or lead to dependence. Additionally, emphasize that lisdexamfetamine be stored in a safe place to prevent misuse and/or abuse. Evaluate patient history (including family history) of abuse of or dependence on alcohol, prescription medicines, or illicit drugs.
• Inform patient that this medication may impair ability to engage in potentially hazardous activities, such as operating machinery or vehicles.
• Advise patients that stimulant therapy at usual doses may cause treatment-emergent psychotic or manic symptoms in patients without a history of these conditions.
• Inform patients who are not growing or gaining weight as expected that they may need to have their treatment interrupted.
• Advise patients of the potential for serious CV risk (including hypertension, MI, and stroke) with lisdexamfetamine.
• Advise patients to notify their health care provider if they become pregnant or intend to become pregnant during treatment. Advise patients not to breast-feed if they are taking lisdexamfetamine.

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