In short: lisdexamfetamine (brand names include Elvanse and Elvanse Adult) is a once-daily stimulant medicine licensed in the UK to treat ADHD in children aged 6 and over and in adults. It is a “prodrug” – inactive until your body converts it into dexamfetamine – which gives a smooth effect lasting up to around 13 hours from a single morning dose. Most people start on 30 mg and adjust weekly to a maximum of 70 mg a day.

This guide, written by a Ready Health prescribing pharmacist, covers how lisdexamfetamine works, dosing, side effects, interactions and practical tips for UK patients.

What is lisdexamfetamine?

Lisdexamfetamine is a central nervous system stimulant. After you swallow it, enzymes in your red blood cells gradually split it into dexamfetamine, the active medicine. Because this conversion is steady, the effect builds gently rather than peaking sharply, and one morning dose usually covers the school or working day.

In the UK it is available as Elvanse (children and adolescents), Elvanse Adult, and generic lisdexamfetamine capsules. It is a Schedule 2 controlled drug.

How does lisdexamfetamine help ADHD?

ADHD is linked with differences in how the brain uses two chemical messengers, dopamine and noradrenaline, in networks responsible for attention, planning and impulse control. Dexamfetamine increases the availability of these messengers, which can help with:

focusing and staying on task
organising and finishing work
reducing impulsivity and restlessness
managing emotions and frustration

Medicine works best alongside practical support such as psychoeducation, coaching, CBT and adjustments at school or work.

Who can take lisdexamfetamine?

Children aged 6 and over: NICE recommends methylphenidate first, with lisdexamfetamine offered if methylphenidate hasn’t helped enough after an adequate trial.
Adults: NICE recommends either lisdexamfetamine or methylphenidate as first-line options.

Treatment should be started by an ADHD specialist. Ongoing prescribing may then be shared with your GP under a shared care agreement.

Lisdexamfetamine may not be suitable if you have certain heart conditions, uncontrolled high blood pressure, overactive thyroid, glaucoma, severe agitation, or have taken an MAOI antidepressant in the last 14 days. Your prescriber will check your blood pressure, pulse and weight (and height in children) before starting.

Lisdexamfetamine dose and timing

Starting dose: usually 30 mg once each morning (sometimes 20 mg).
Adjusting: the dose can be increased by 10–20 mg at roughly weekly intervals until you reach the dose that gives the best balance of benefit and side effects.
Maximum licensed dose: 70 mg once a day.
Onset: usually within 1–2 hours.
Duration: up to around 13 hours.

Some women notice ADHD symptoms worsen before a period. If this happens, keep a symptom diary and discuss it with your prescriber rather than changing your dose yourself.

How to take lisdexamfetamine

Take it once a day in the morning, with or without food. Avoid afternoon doses, as they can keep you awake.
Swallow the capsule whole with a drink of water.
If swallowing is difficult, open the capsule and mix the contents into soft food such as yoghurt, or into a glass of water or orange juice. Break up any clumps, stir well and take it all straight away. A thin film left in the glass is normal.
Don’t split the contents of a capsule to take a smaller dose.

Missed doses and taking too much

Missed dose: if you remember in the morning, take it then. If it’s already afternoon, skip it and take your usual dose the next morning. Never take two doses to make up for a missed one.
Taken an extra dose by mistake: you may feel restless, jittery, sweaty or unable to sleep, or notice a headache or racing heart. Avoid driving, alcohol and strenuous exercise, and contact your prescriber, pharmacist or NHS 111 for advice.
Large overdose, chest pain, fits, confusion or collapse: call 999 or go to A&E.

Side effects of lisdexamfetamine

Side effects are often dose-related and many settle in the first few weeks.

Common

reduced appetite and weight loss
difficulty sleeping
dry mouth
headache
stomach ache or nausea
feeling irritable, anxious or restless
a faster heart rate or small rise in blood pressure

Contact your prescriber promptly if you notice

persistent sleep problems, mood swings, low mood or aggression
new or worsening tics
palpitations or consistently raised blood pressure
cold, painful, pale or blue fingers or toes (Raynaud’s-type symptoms)
new or worsening anxiety, or unusual thoughts

Call 999 or go to A&E if you have

chest pain, fainting or a very fast or irregular heartbeat
a seizure (fit)
signs of a severe allergic reaction, such as swelling of the face or throat, or difficulty breathing
high temperature, confusion, sweating, shaking and muscle jerks – possible serotonin syndrome

Interactions and cautions

Tell your prescriber and pharmacist about everything you take, including over-the-counter and herbal products. Take particular care with:

MAOI antidepressants – must not be taken together or within 14 days of each other
Serotonergic medicines such as SSRIs, SNRIs, tramadol and triptans – small risk of serotonin syndrome
Decongestants and other stimulants, including some cold remedies and “energy” or weight-loss products
Medicines that change urine acidity – high-dose vitamin C can reduce the effect, while antacids such as sodium bicarbonate can increase it
Blood pressure medicines – lisdexamfetamine may reduce their effect
Alcohol – can worsen side effects and is best avoided or kept to a minimum

Lisdexamfetamine and driving in the UK

Amfetamine is one of the drugs covered by UK drug-driving law. It is legal to drive if you take lisdexamfetamine as prescribed and it does not impair your driving. Carry your prescription or a letter from your prescriber, and don’t drive if you feel affected. You must also tell the DVLA if your ADHD affects your ability to drive safely.

Is lisdexamfetamine addictive?

Any stimulant can be misused. Because lisdexamfetamine has to be converted in the blood, it produces a slower, smoother effect than immediate-release amfetamines, which is thought to reduce its potential for misuse. Research suggests that treating ADHD does not increase the later risk of substance misuse. Keep your medicine secure and never share it – it is a controlled drug.

How long will I need to take it?

Many people take lisdexamfetamine for months or years. NICE recommends a review at least once a year to check whether you still need it, the dose is right and your blood pressure, pulse and weight are fine. Some people take planned breaks, for example during school holidays, but only after discussing this with their prescriber.

Can I stop taking lisdexamfetamine suddenly?

Lisdexamfetamine can usually be stopped without tapering, but some people notice tiredness, low mood, increased appetite or a return of ADHD symptoms. If you are on a higher dose or have taken it for a long time, your prescriber may suggest reducing gradually. Talk to your prescriber before stopping.

Pregnancy and breastfeeding

If you are planning a pregnancy, are pregnant or are breastfeeding, speak to your prescriber before making any changes. See our guide to dexamfetamine and lisdexamfetamine in pregnancy and breastfeeding.

Alternatives if lisdexamfetamine doesn’t suit you

Other stimulants: methylphenidate (several modified-release brands) or dexamfetamine
Non-stimulants: atomoxetine, or guanfacine (licensed in the UK for children and young people aged 6–17)
Non-medicine support: ADHD coaching, CBT and reasonable adjustments at school or work

Frequently asked questions

How long does lisdexamfetamine take to work?

Each dose starts working within 1–2 hours. Finding the right dose usually takes a few weeks of gradual adjustment.

Is Elvanse the same as lisdexamfetamine?

Yes. Elvanse and Elvanse Adult are brand names for lisdexamfetamine. Generic lisdexamfetamine capsules contain the same active ingredient.

What is the difference between lisdexamfetamine and dexamfetamine?

Lisdexamfetamine is converted into dexamfetamine in the body, giving a smoother, longer effect from one daily dose. Dexamfetamine tablets act more quickly and usually need to be taken two or three times a day.

Can I drink alcohol on lisdexamfetamine?

It’s best to avoid alcohol or keep it to a minimum, as it can worsen side effects such as a racing heart, poor sleep and low mood.

Does lisdexamfetamine cause weight loss?

Reduced appetite is common, particularly in the first few months. Eating a good breakfast before your dose and a substantial evening meal can help. Your weight will be checked regularly.

Key takeaways

Lisdexamfetamine is a once-daily ADHD stimulant licensed in the UK for children aged 6+ and adults.
Start low (usually 30 mg) and adjust weekly to a maximum of 70 mg, taken in the morning.
Common side effects include reduced appetite, poor sleep and headache; most settle with time or a dose change.
Avoid MAOIs, take care with other serotonergic medicines, and attend regular reviews.

Sources and further reading

Last reviewed: October 2026 by Shamir Patel, Independent Prescribing Pharmacist, Ready Health. This article is general information and does not replace advice from your own prescriber or pharmacist. Brand names are trademarks of their respective owners.

Need help with ADHD? Ready Health offers ADHD assessments, medication titration and reviews with experienced clinicians. Find out more or book an appointment.

Lisdexamfetamine (Elvanse) for ADHD: Dose, Side Effects and UK Patient Guide