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Melatonin tablets for insomnia

Adaflex, Circadin

Melatonin is useful in helping to promote sleep in people over the age of 55 years who have difficulty sleeping. It also helps to promote sleep in children with learning difficulties such as Autism Spectrum Disorder (ASD) and ADHD.

Take one 2 mg tablet 1-2 hours before bedtime, with a snack.

Melatonin will make you feel sleepy, so do not drive and do not use tools or machines until this effect has worn off.

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About melatonin

Type of medicine

Hypnotic (sleeping tablet)

Used for

Poor sleep

Also called

Adaflex®; Ceyesto®; Circadin®; Civasta®; Slenyto®; Syncrodin®

Available as

Modified-release tablets, tablets, capsules and oral liquid medicine

Poor sleep can mean that you have difficulty getting to sleep, or that you wake up for long periods during the night, or that you wake early, or that you do not feel refreshed in the mornings.

Insomnia is a fairly common condition, but it does not usually last for long. Melatonin is a hormone which occurs naturally in the body and is associated with the control of the body's sleep pattern. As we grow older the amount of naturally occurring melatonin in the body reduces. Taking melatonin adds to the body's natural supply and helps to promote and improve the quality of sleep.

Circadin® and Civasta® tablets are prescribed for people over the age of 55 years who have insomnia, or difficulty sleeping.

Slenyto® tablets are prescribed for poor sleep in children between the ages of 2 years and 18 years with Autism Spectrum Disorder (ASD) or Smith-Magenis syndrome.

Adaflex® and Ceyesto® tablets are prescribed for poor sleep in children aged 6 to 17 years with ADHD. They can also be prescribed for adults who experience jet lag.

Syncrodin® tablets are prescribed for adults who experience jet lag.

Sometimes a doctor may prescribe melatonin for other groups of people with sleeping problems. If this is the case for you, the way you take melatonin and your dose may be different from the information in this leaflet. Follow your doctor's instructions carefully and ask your doctor or pharmacist if you are unsure of anything.

Before taking melatonin

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking melatonin it is important that your doctor or pharmacist knows:

  • If you have any problems with the way your liver works, or with the way your kidneys work.

  • If you have an autoimmune disease - a condition in which the body is attacked by its own overactive immune system. It includes conditions such as rheumatoid arthritis, multiple sclerosis, and lupus.

  • If you are taking any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines.

  • If you have ever had an allergic reaction to a medicine.

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How to take melatonin

  • Before you start the treatment, read the manufacturer's printed information leaflet from inside the pack. It will give you more information about melatonin and will provide you with a full list of the side-effects which you may experience from taking it.

  • Take melatonin exactly as your doctor tells you to. For adults the dose is usually one 2 mg tablet daily, taken 1-2 hours before bedtime. For children with ASD the usual starting dose is 2 mg taken 30 minutes to one hour before bedtime. Your child's doctor may increase the dose slowly to get a better response.

  • Take the tablet with a snack or after eating some food. This will help the medicine to work later into the night. Swallow the tablet whole - do not break or crush the tablet because it is designed to release melatonin slowly over a few hours.

  • If you forget to take a tablet at the usual time but you remember before you go to sleep, take it when you remember. If you do not remember until the following day, just take the next dose as usual. Do not take two doses together to make up for a forgotten dose.

Getting the most from your treatment

  • Do not take melatonin for longer than your doctor advises. It can be prescribed for up to 13 weeks for adults over 55.

  • Do not drink alcohol while you are taking melatonin because it will reduce the medicine's effectiveness in helping you to sleep.

  • Try to keep your regular appointments with your doctor. This is so your progress can be monitored.

  • There are some general recommendations that may help promote good sleep. Try to reduce the amount of caffeine you drink, especially in the afternoon and evening. Try to avoid eating heavy meals or drinking alcohol before bedtime. Exercise early in the day, rather than in the evening.

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Can melatonin cause problems?

Along with their useful effects, most medicines can cause unwanted side-effects but not everyone experiences them. The table below contains some of the side-effects associated with melatonin. Children may be more likely than adults to experience these side-effects. You will find a full list in the manufacturer's information leaflet supplied with your medicine. The unwanted effects often improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following continue or become troublesome.

Melatonin side-effects (these affect fewer than 1 in 10 people)

What can I do if I experience this?

Feeling tired or sleepy

Do not drive and do not use tools or machines until these effects have worn off


Drink plenty of water and ask a pharmacist to recommend a suitable painkiller. If the headaches continue, let your doctor know

Indigestion, feeling sick (nausea), stomach ache

Stick to simple foods - avoid rich or spicy meals

Feeling irritable or restless, mood swings, dry mouth, abnormal dreams, night sweats, dry or itchy skin, pains in the arms or legs

If any of these become troublesome, speak with your doctor

If you experience any other symptoms which you think may be due to the tablets, speak with your doctor or pharmacist for further advice. Children with ASD may be more likely to experience mood swings, irritability or aggression when taking melatonin.

How to store melatonin

  • Keep all medicines out of the reach and sight of children.

  • Store in a cool, dry place, away from direct heat and light.

Important information about all medicines

Important information about all medicines

Never take more than the prescribed dose. If you suspect that you or someone else might have taken an overdose of this medicine, go to the accident and emergency department of your local hospital at once. Take the container with you, even if it is empty.

This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.

If you are having an operation or dental treatment, always tell the person carrying out the treatment which medicines you are taking.

If you buy any medicines, check with a pharmacist that they are safe to take with your other medicines.

Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.

If you have any questions about this medicine ask your pharmacist.

Report side effects to a medicine or vaccine

If you experience side effects, you can report them online through the Yellow Card website.

Further reading and references

Article history

The information on this page is written and peer reviewed by qualified clinicians.

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