• Melatonin is useful in helping to promote sleep in people over the age of 55 years who have difficulty sleeping.
  • The usual dose is one tablet taken 1-2 hours before bedtime.
  • Take melatonin after food and swallow the tablets whole without chewing or breaking them.
  • Melatonin will make you feel sleepy so do not drive or use tools until this effect has worn off.
Type of medicine Hypnotic
Used for Insomnia
Also called Circadin®
Available as Modified-release tablets

Melatonin is used to treat insomnia (difficulty sleeping), but only for a period of time of up to 13 weeks. It is licensed for use in people who are over the age of 55 years.

Melatonin is a hormone which occurs naturally in the body and is associated with the control of the body's sleep pattern. It works in insomnia by helping to promote and improve the quality of sleep. It is effective in people over the age of 55 years because as we grow older the amount of naturally occurring melatonin reduces.

Before taking melatonin make sure your doctor or pharmacist knows:

  • If you have liver or kidney problems.
  • If you have an autoimmune disease. This is where the body is attacked by its own overactive immune system. It includes conditions such as rheumatoid arthritis, multiple sclerosis, and lupus.
  • If you are pregnant or breast-feeding.
  • If you are taking other medicines, including those available to buy without a prescription, herbal and complementary medicines.
  • If you have ever had an allergic reaction to this or to any other medicine.
  • Before starting this treatment, read the manufacturer's printed information leaflet from inside the pack.
  • Take melatonin exactly as your doctor has told you. The usual dose is one tablet each day taken 1-2 hours before bedtime.
  • Take melatonin with a snack or just after food.
  • Swallow the tablets whole, do not chew or crush them. This is because the tablets are designed to release the melatonin slowly for a more even effect.
  • If you forget to take a dose, take it as soon as you remember if it is before you go to sleep. If you do not remember until the following day, skip the missed dose and take the next dose when it is due.
  • Do not drink alcohol while you are taking melatonin because it will reduce the medicine's effectiveness in helping you sleep.
  • Try to keep your regular appointments with your doctor. This is so your progress can be monitored.
  • If you are having an operation or dental treatment, 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.

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. These usually improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following side-effects continue or become troublesome.

These side-effects are considered to be uncommon - this means they affect fewer than 1 in 100 people who take this medicine What can I do if I experience this?
Drowsiness, dizziness, tiredness If this happens, do not drive or use tools or machines until these effects have worn off and your reactions have returned to normal
Indigestion, stomach ache Eat little and often, and try to avoid rich or spicy foods
Dry mouth, mouth ulcers Ask your pharmacist to recommend a preparation to help this
Feeling irritable or restless, night sweats, dry or itchy skin, skin rash, 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 this medicine, discuss them with your doctor or pharmacist.

  • Keep all medicines out of the reach and sight of children.
  • Store in a cool, dry place, away from direct heat and light.
  • Never take more than the prescribed dose. If you suspect that someone has 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.
  • Never 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.

Further reading & references

  • British National Formulary; 62nd Edition (Sep 2011) British Medical Association and Royal Pharmaceutical Society of Great Britain, London
  • Manufacturer's PIL, Circadin® 2 mg prolonged-release Tablets; Manufacturer's PIL, Circadin® 2 mg prolonged-release Tablets, Lundbeck Limited, electronic Medicines Compendium. Dated August 2011.

Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. EMIS has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions.

Original Author:
Helen Allen
Current Version:
Peer Reviewer:
Dr Helen Huins
Last Checked:
Document ID:
13785 (v1)
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