Lisdexamfetamine: Prodrug Stimulant for ADHD and Binge Eating Disorder
Lisdexamfetamine (Vyvanse/Elvanse) is a prodrug of d-amphetamine, requiring enzymatic cleavage to active dexamphetamine after oral ingestion. This delays onset and prolongs duration (up to 14 hours), reducing abuse potential compared to immediate-release amphetamines.
Approved for ADHD in children (6+), adolescents, and adults; and for binge eating disorder (BED) in adults. Considered among the most effective stimulant medications for ADHD.
Mechanism of Action
Dexamphetamine reverses monoamine transporters, causing release of dopamine and norepinephrine from presynaptic terminals (reverse transport), increasing synaptic concentrations. Also weakly inhibits MAO. Leads to improved attention, working memory, and impulse control.
Indications & Use
ADHD (moderate to severe, children ≥6 years, adolescents, adults). Binge eating disorder (adults). First-line alongside methylphenidate for ADHD; preferred when 12+ hour coverage or abuse deterrence is needed.
Dosage
ADHD: start 20–30 mg/day (children), 30 mg/day (adults). Titrate weekly by 10–20 mg. Maximum 70 mg/day. BED: start 30 mg/day, titrate to 50–70 mg/day. Take in morning (insomnia if taken late).
Side Effects
Common: decreased appetite, insomnia, headache, dry mouth, irritability, elevated heart rate and blood pressure. Growth suppression in children (monitor height/weight). Rarely: cardiovascular events in pre-existing cardiac disease.
Drug Interactions
MAOIs: contraindicated — hypertensive crisis (fatal). Antihypertensives: may reduce efficacy. Acidifying agents (vit. C, antacids): reduce amphetamine levels. Alkalising agents (sodium bicarbonate): increase levels. SSRIs/SNRIs: serotonin syndrome risk.
Contraindications
Symptomatic cardiovascular disease, moderate-severe hypertension, hyperthyroidism, glaucoma, current or recent MAOI use, history of drug abuse. Avoid in pregnancy.
Frequently Asked Questions
Why is lisdexamfetamine less abusable than regular amphetamine?
Lisdexamfetamine must be enzymatically cleaved in the gut/blood to release active dexamphetamine. Injecting or snorting the prodrug does not accelerate onset (no 'rush'), which significantly reduces its abuse potential.
Does lisdexamfetamine stunt growth in children?
Growth suppression has been observed, particularly in the first 1–2 years of treatment. Growth is usually recovered after treatment ends. Annual monitoring of height and weight is recommended. Drug holidays during school breaks may be considered.
How long does lisdexamfetamine last?
The duration of action is approximately 12–14 hours, significantly longer than methylphenidate. This single-dose coverage is a key advantage for school and evening activities.
References
- NICE NG87: ADHD 2018 (updated 2023)
- EMA Elvanse SPC 2023
- Faraone SV et al. World Psychiatry 2015
Medical Disclaimer: This information is for educational purposes only and does not replace professional medical advice.