Melatonin is the natural hormone your body secretes that helps to maintain your wake-sleep cycle (also called “biological clock”). The wake-sleep cycle is the process of sleep and wakefulness; in humans this averages 8 hours of nighttime sleep and 16 hours of daytime activity. 

How Does Melatonin Work?

Natural melatonin is a highly lipid soluble hormone produced in the pineal gland in the brain. It is synthesized from the amino acid tryptophan and then released into the blood and cerebrospinal fluid, crossing the blood-brain barrier. It sends messages to the receptor agonist in the brain and other areas of the body to help control the sleep and wake cycles.

Why is it important for my child to take this medicine?

  • Poor sleep can affect your child’s physical health, mood, behaviour and development. Melatonin is used to help regulate the sleep pattern of children. Melatonin may help your child to get into a regular sleep pattern.

When should I give melatonin?

  • Melatonin is best given once a day, between half an hour and an hour before your child’s agreed bedtime.
  • Give the medicine at about the same time each day so that this becomes part of your child’s daily routine, which will help you to remember.

How much should I give?

  • Your doctor will work out the amount of melatonin (the dose) that is right for your child. The dose will be shown on the medicine label.
  • Your doctor will probably recommend that your child has a low dose to start with. They may then increase the dose until your child’s sleep problems have improved. Normally, the dose will not be more than 10 mg per day.

When should the medicine start working?

  • Melatonin should start to make your child feel sleepy about half an hour to an hour after taking a dose.

What if my child is sick (vomits)?

  • If your child is sick less than 30 minutes after having a dose of melatonin, give them the same dose again.
  • If your child is sick more than 30 minutes after having a dose of melatonin, you do not need to give them another dose that night.

What if I forget to give it?

  • If you miss a dose and your child is already asleep, wait until the next day and give the normal dose as usual. If your child is still awake, give them the normal dose.

What if I give too much?

  • If you think you may have given your child too much melatonin, contact your doctor.
  • Take the medicine container or packaging with you, even if it is empty. This will be useful to the doctor. 

Are there any possible side-effects?

  • Rarely, melatonin can cause problems with your child’s heart. If your child develops a severe chest pain or has a fast heart rate (they may have a fluttering feeling in their chest or feel their heart beating fast), contact your doctor straight away or take your child to hospital.
  • If your child seems very unwell in any way that is unusual for them and you are concerned, take them to hospital.

Other side-effects you need to know about

  • Your child may feel dizzy or nervous, or may have stomach pain.
  • Your child may develop a rash and itch.
  • If you are concerned about any of these side-effects contact your doctor.

Can other medicines be given at the same time as melatonin?

  • You can give your child medicines that contain paracetamol or ibuprofen, unless your doctor has told you not to.
  • Check with your doctor or pharmacist before giving any other medicines to your child. This includes herbal or complementary medicines.

Is there anything else I need to know about this medicine?

  • Treatment with melatonin is usually started by a specialist.

General advice about medicines

  • Only give this medicine to your child. Never give it to anyone else, even if their condition appears to be the same, as this could do harm.
  • If you think someone else may have taken the medicine by accident, contact your doctor straight away.

Where should I keep this medicine?

  • Keep the medicine in a cupboard, away from heat and direct sunlight. It does not need to be kept in the fridge.
  • Make sure that children cannot see or reach the medicine.
  • Keep the medicine in the container it came in.



Health Reference: Insomnia