Last updated: October 2026
No, you can’t buy melatonin over the counter in the UK. It is a prescription-only medicine, usually prescribed as 2mg slow-release tablets for adults aged 55 and over with short-term insomnia, for up to 13 weeks. It isn’t illegal to own, but UK shops can’t legally sell it, and the NHS advises against ordering it online.
This guide explains why melatonin is prescription-only here, how to get it, what the research says about how well it works, and the alternatives you can buy legally.
Is melatonin legal in the UK?
Yes, melatonin is legal, but only as a prescription medicine. You can’t buy it from a supermarket, health food shop or pharmacy counter without a prescription, and UK sellers can’t legally sell melatonin supplements or gummies.
| UK | US | |
|---|---|---|
| How it is classed | Prescription-only medicine | Dietary supplement |
| Where you get it | GP, specialist or registered online prescriber | Supermarkets, pharmacies, online |
| Usual form | 2mg slow-release tablets | Tablets and gummies, often 3 to 10mg |
| Quality control | Licensed medicine, checked dose | Supplement, dose often differs from the label |
Why is melatonin prescription-only in the UK?
Melatonin isn’t banned. It is a hormone your body makes naturally, and taking it as a tablet has a direct effect on how your body works. That is why the UK medicines regulator, the MHRA, treats it as a medicine rather than a food supplement. Medicines have to be licensed, made to a checked standard and supplied by a prescriber who can decide if they are right for you.
There are good reasons for caution. It can interact with other medicines, isn’t suitable for some people (such as those with autoimmune conditions or liver problems), and unlicensed supplements are often inaccurately labelled. In a Canadian study of 31 melatonin supplements, the actual melatonin content ranged from 83% less to 478% more than the label said.
How to get melatonin in the UK
| Who | What may be prescribed | How long |
|---|---|---|
| Adults 55 and over with short-term insomnia | 2mg slow-release tablet (such as Circadin), 1 to 2 hours before bed | Usually 1 to 4 weeks, up to 13 weeks |
| Adults under 55 with longer-term sleep problems | On a specialist’s advice, for example with ADHD | Can be longer term |
| Children and teenagers | On a specialist’s advice, such as Slenyto for some autistic children | Specialist-led |
| Jet lag in adults | 3mg standard tablet (such as Adaflex), often a private prescription | Up to 5 days per trip |
Start with your GP. Many GPs will first suggest changes to your sleep habits or cognitive behavioural therapy for insomnia (CBT-I), which is the recommended first treatment for long-term insomnia. Registered online pharmacies can also supply melatonin on a private prescription after an online consultation; check they are registered with the General Pharmaceutical Council.
Buying melatonin online or abroad
Many people buy melatonin gummies on holiday in the US or order them from overseas websites. Owning melatonin isn’t a criminal offence, but the NHS advises against ordering it online, and websites selling it to UK customers without a prescription are breaking the law.
The bigger issue is quality. Overseas supplements aren’t checked to UK medicine standards. A 2023 US analysis of melatonin gummies found most contained a different amount from the label, and some also contained CBD that wasn’t listed. If you want to try melatonin, a prescription is the safest route. Read more about melatonin vs CBD.
Does melatonin work?
It works, but modestly. A review of 19 controlled trials found melatonin helped people fall asleep about 7 minutes faster and sleep about 8 minutes longer than placebo, with slightly better sleep quality. The benefit didn’t wear off with continued use.
Melatonin is best at shifting the timing of sleep rather than knocking you out. That’s why it is used for jet lag and body-clock problems. If stress, a racing mind, pain or poor sleep habits are keeping you awake, melatonin may not tackle the cause. The NHS says melatonin takes around 1 to 2 hours to work.
Side effects and who should avoid it
Most people don’t get side effects. The more common ones are daytime sleepiness, headache, stomach ache, feeling sick, dizziness and irritability. Don’t drive if it makes you drowsy.
Tell your doctor before taking melatonin if you have liver or kidney problems, or an autoimmune condition such as rheumatoid arthritis, multiple sclerosis or lupus. Alcohol and smoking can stop it working as well.
The NHS advises not to take herbal remedies that may affect sleep at the same time as melatonin, as you could become very drowsy. That includes sleep products with passionflower, chamomile, hops or valerian. If you are prescribed melatonin, check with your doctor or pharmacist before adding any sleep supplement, including CBD.
Melatonin alternatives you can buy in the UK
None of these is a substitute for prescribed treatment, and none works in the same way as melatonin. But many people find them helpful as part of an evening routine.
| Option | What it is | Good to know |
|---|---|---|
| Magnesium | A mineral; glycinate is the gentlest form | Contributes to the normal functioning of the nervous system and normal psychological function. See magnesium for sleep |
| CBD | A non-intoxicating hemp compound | Research is early; many people use it in the evening. See CBD for sleep |
| L-theanine | An amino acid found in tea | Popular for a calm evening. See L-theanine benefits |
| Tart cherry | A fruit that naturally contains small amounts of melatonin | Small studies only; as juice or concentrate |
| Chamomile, passionflower, valerian | Traditional herbal remedies | Look for the THR mark on herbal medicines |
Our Magnesium Glycinate Sleep Complex combines magnesium bisglycinate and citrate with glycine, L-theanine and botanicals as a warm evening drink. Our Sleep CBD Oil pairs broad spectrum CBD with passionflower. Compare options in our best CBD oil for sleep guide.
Ways to boost your own melatonin
Your body makes melatonin as it gets dark. You can help it along:
- Get daylight in the morning. Bright light early in the day helps set your body clock, so melatonin rises at the right time in the evening.
- Dim the lights in the evening and cut back on screens in the hour before bed.
- Keep regular hours, including at weekends.
- Keep your bedroom dark, with blackout blinds or an eye mask.
- Cut back on alcohol and late caffeine, which both disrupt sleep.
The clocks go back on 25 October, which can unsettle sleep for a week or so. See our guide to sleeping well when the clocks go back, plus natural remedies for insomnia.
FAQs
Can you buy melatonin over the counter in the UK?
No. Melatonin is a prescription-only medicine in the UK, so you need a prescription from a GP, specialist or registered online prescriber.
Why is melatonin banned in the UK?
It isn’t banned. It is classed as a medicine rather than a supplement, because it is a hormone with a direct effect on the body, so it is only available on prescription.
Is it illegal to bring melatonin into the UK?
Owning melatonin isn’t a criminal offence, and many people bring it back from the US. But UK sellers can’t legally supply it without a prescription, and the NHS advises against buying it online because quality can’t be guaranteed.
Are melatonin gummies legal in the UK?
They can’t legally be sold in the UK. Any melatonin product, including gummies, is a medicine here and needs a prescription.
Can I get melatonin from my GP?
Possibly. GPs mainly prescribe it for adults aged 55 and over with short-term insomnia. Younger adults and children usually need a specialist’s recommendation.
What is the best melatonin alternative in the UK?
There’s no direct equivalent you can buy. Many people use magnesium, CBD, L-theanine or herbal remedies as part of an evening routine, alongside good sleep habits.
Can I take magnesium with melatonin?
Plain magnesium is generally fine, but the NHS advises against herbal sleep remedies alongside melatonin, and many magnesium sleep blends contain herbs. Check with your doctor or pharmacist first.
Sources
- NHS. Melatonin, including common questions.
- NHS. Insomnia.
- Ferracioli-Oda E et al (2013). Meta-analysis: melatonin for the treatment of primary sleep disorders. PLoS One.
- Erland LA, Saxena PK (2017). Melatonin natural health products and supplements: presence of serotonin and significant variability of melatonin content. Journal of Clinical Sleep Medicine.
- Cohen PA et al (2023). Quantity of melatonin and CBD in melatonin gummies sold in the US. JAMA.
This guide is general information, not medical advice. Evopure makes sleep supplements but does not sell melatonin.
