LISDEXAMFETAMINE DIMESYLATE (lis-dex-am-fet'a-meen)
Vyvanse Classifications: cerebral stimulant; amphetamine; anorexigenic; Therapeutic: cerebral stimulant Prototype: Amphetamine Pregnancy Category: C Controlled Substance: Schedule II
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Availability
30 mg, 50 mg, and 70 mg capsules
Action
An isomer of amphetamine that has anorexigenic action; this is thought to result from CNS stimulation and possibly from
loss of acuity of smell and taste. CNS stimulating effect is approximately twice that of racemic amphetamine.
Therapeutic Effect
In hyperkinetic children, amphetamines reduce motor restlessness by an unknown mechanism.
Uses
Treatment of attention-deficit hyperactivity disorder (ADHD).
Contraindications
Hypersensitivy to sympathomimic amines, or amphetamine; advanced arteriosclerosis; structural cardiac abnormalities, cardiomyopathy,
cardiac arrhythmias, or symptomatic cardiovascular disease; moderate to severe hypertension; glaucoma; agitated states;
patients with history of drug abuse; during or within 14 d of administering MAOIs; hyperthyroidism; history of depression
or suicide; seizure disorders; tics or Tourette syndrome; pregnancy (category C); lactation; children <3 y.
Cautious Use
Controlled hypertension, heart failure, recent MI, or recent ventricular arrhythmia; preexisting psychotic disorder; bipolar
disorder; history of aggressive or hostile behavior.
Route & Dosage
Attention-Deficit Hyperactivity Disorder Child (612 y): PO 30 mg q.d. in a.m.; may increase to 5070 mg q.d. at weekly intervals (max: 70 mg q.d.)
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Administration
Oral
- Give daily dose in the morning.
- Capsule may be taken whole or opened and dissolved in a glass of water.
- Store at 15°30° C (59°86° F) and protect from light.
Adverse Effects (≥1%)
Body as a Whole: Pyrexia.
CNS: Affect lability, dizziness,
headache, insomnia, irritability, somnolence, tic.
GI: Abdominal pain, dry mouth, nausea, vomiting.
Metabolic: Decreased appetite, weight loss.
Skin: Rash.
Diagnostic Test Interference
Lisdexamfetamine can cause a significant elevation in plasma corticosteroid levels and may interfere with urinary steroid determinations.
Interactions
Drug: Chlorpromazine and
haloperidol inhibit the
CNS stimulant effects of amphetamines.
Furazolidone decreases amphetamine metabolism and can increase adverse effects.
Lithium may inhibit the effects of lisdexamfetamine.
monoamine oxidase inhibitors will increase plasma levels of lisdexamfetamine.
Propoxyphene can potentiate the
CNS stimulation of lisdexamfetamine. Compounds that acidify the urine lower the plasma levels of lisdexamfetamine.
Lisdexamfetamine inhibits the actions of
adrenergic blockers. Co-administration of
antihistamines with lisdexamfetamine can counteract desired sedative effects. Lisdexamfetamine may antagonize the hypotensive effects
of
antihypertensive agents. Lisdexamfetamine may delay the absorption of
ethosuximide and
phenytoin. Lisdexamfetamine may potentiate the actions of
tricyclic antidepressants,
meperidine and
norepinephrine.
Pharmacokinetics
Absorption: Rapidly absorbed from GI tract.
Peak: 1 h.
Distribution: Extensive throughout body.
Metabolism: Prodrug converted in liver to dextroamphetamine.
Elimination: Urine (96%).
Half-Life: 1 h (lisdexamfetamine) 68 h (dextroamphetamine).
Nursing Implications
Assessment & Drug Effects
- Monitor children, adolescents, and adults for signs and symptoms of adverse cardiac reactions (e.g., hypertension, arrhythmias).
Report promptly exertional chest pain or syncope.
- Monitor closely growth rate in children.
- Typically therapy is interrupted or dosage reduced periodically to assess effectiveness in behavior disorders.
- Monitor children and adolescents for development of aggressive or abnormal behaviors.
Patient & Family Education
- Do not drive or engage in other potentially hazardous activities until response to drug is known.
- Report promptly any of the following: chest pain with activity, new or worse behavior or thought problems, psychotic symptoms
(e.g., hearing voices, believing things that are not true).
- Taper drug gradually following long-term use to avoid extreme fatigue, mental depression, and prolonged abnormal sleep pattern.