Why melatonin may be dangerous to your sleep

For More Information. Key References. Journal of Pineal Research. The safety of melatonin in humans. Clinical Drug Investigation. In-silico drug repurposing study predicts the combination of pirfenidone and melatonin as a promising candidate therapy to reduce SARS-CoV-2 infection progression and respiratory distress caused by cytokine storm. PLoS One. An update for Journal of Clinical Sleep Medicine. Evidence for the efficacy of melatonin in the treatment of primary adult sleep disorders.

Sleep Medicine Reviews. Virus Research. The effectiveness of melatonin for promoting healthy sleep: a rapid evidence assessment of the literature. Nutrition Journal. Pediatric sleep disturbances and treatment with melatonin. Journal of Translational Medicine. Melatonin for pre- and postoperative anxiety in adults. Cochrane Database of Systematic Reviews. Accessed at www. Matrix metallopeptidase 9 as a host protein target of chloroquine and melatonin for immunoregulation in COVID a network-based meta-analysis.

Life Sciences. Herxheimer A. Clinical Evidence. Kennaway D. Potential safety issues in the use of the hormone melatonin in paediatrics. Journal of Paediatrics and Child Health. Pharmacological interventions for sleepiness and sleep disturbances caused by shift work. Pharmacologic treatments for sleep disorders in children: a systematic review. Journal of Child Neurology. Turkish Journal of Medical Sciences. Management of chronic insomnia disorder in adults: a clinical practice guideline from the American College of Physicians.

Annals of Internal Medicine. Clinical practice guideline for the pharmacologic treatment of chronic insomnia in adults: an American Academy of Sleep Medicine clinical practice guideline. Molecular Biological Reports. Tan D-X, Hardeland R. Targeting host defense system and rescuing compromised mitochondria to increase tolerance against pathogens by melatonin may impact outcome of deadly virus infection pertinent to COVID A network medicine approach to investigation and population-based validation of disease manifestations and drug repurposing for COVID PLoS Biology.

Evaluation of the efficacy and safety of melatonin in moderately ill patients with COVID a structured summary of a study protocol for a randomized controlled trial.

Other References. Barion A, Zee PC. A clinical approach to circadian rhythm sleep disorders. One review suggests the following age-based dosages 30 to 60 minutes before bedtime:. The amount of melatonin your body produces decreases with age.

Because of this, melatonin supplements may be helpful for older adults who are having trouble falling asleep. Researchers are still looking into the optimal melatonin dosage for older adults. One review of sleep aids for older adults suggests a dosage of 1 to 2 mg of immediate-release melatonin 1 hour before bedtime. Additionally, 26 percent of products contained serotonin , which can be potentially harmful even in small doses.

However, information on the effects of long-term melatonin supplements is limited. Some studies have indicated that long-term melatonin use in adults may cause mild side effects when compared to a placebo.

Studies into the effects of long-term melatonin use in children remains limited. However, more research is needed. Melatonin is generally safe. However, mild side effects can sometimes occur, particularly if you take higher doses or extended-release formulations. The side effects of melatonin can include:. If you experience side effects from melatonin , stop taking it and speak with your doctor.

They may recommend using a lower dose or trying out an alternative medication or sleep aid. Can you take another dose? In particular, it may be useful for migraine and cluster headaches. However, researchers do not know which formula and dose might work best for people with headaches. Some clinical studies of colon, breast, renal, brain, and lung cancer suggest that melatonin might support cancer treatment when a person takes it alongside chemotherapy and radiation therapy.

However, the evidence is far from definitive, and scientists need to carry out more research to confirm the link. The available evidence suggests that melatonin may help combat cancer when it starts, multiplies, and progresses. There are many ways in which this supplement may work on cancer. Anyone wanting to take melatonin should discuss it with their cancer doctor, or oncologist, to make sure it will not interfere with their cancer treatments.

Melatonin levels decrease with age. The findings of a study suggested that melatonin might slightly improve the symptoms of tinnitus.

This effect may be due to improved sleep or the antioxidant properties of melatonin. Radiation therapy plays a key role in treating many types of cancer.

However, it is toxic and can cause severe side effects. Much of the damage radiation causes is due to harmful substances called free radicals. Melatonin is an antioxidant that helps combat the damaging effects of free radicals, plus it has anticancer effects. Some research suggests that it might provide benefits for people who receive radiation therapy during cancer treatment. Always talk to an oncologist before taking melatonin to ensure sure it does not interfere with other treatments.

Learn how melatonin might work to improve sleep. Most doctors, healthcare providers, and other experts consider melatonin as generally safe. However, it can cause side effects when people take it in more than the recommended amounts. Taking too much of this supplement could lead to an accidental overdose. To avoid this, people should take the correct dose for their age.

Anyone thinking about taking melatonin should check with their doctor to make sure it is safe for them. Symptoms of a melatonin overdose vary from person to person. In some people, taking too much melatonin can increase sleepiness. In others, it can have the opposite effect and produce a state of enhanced alertness. Melatonin can lead to a spike in blood pressure if a person takes more than the recommended dose.

If a person already has high blood pressure , they should check with a doctor before taking this product. People who take this supplement should report any unusual side effects to their doctor. Researchers have not yet worked out the most effective dosages of melatonin, so no clear guidelines exist. A usual dose in adults is 1—5 milligrams mg , depending on the use, but doses can vary from 0. In some cases, a low dose may work better than a high dose. A small dose of around 0. Larger doses cause much higher levels of melatonin in the blood.

In children , use the lowest dosage to begin with. In many cases, a child will respond to 0. If a child is still unable to sleep within 1 hour of their bedtime, increase the dosage by 0. Younger children often take 1—3 mg at a time, while older children and teens may need slightly higher dosages. Those with significant difficulty falling asleep may benefit from dosages of 3—6 mg.

According to the National Institute for Health and Care Excellence , people should take modified-release tablets with food or after eating, but they should take immediate-release formulations on an empty stomach, 2 hours before or after eating.

Learn which factors help determine the right dosage of melatonin. Melatonin appears to be safe for the short-term treatment of sleep issues. Its long-term safety is not as clear. Scientists have not done enough research to confirm whether it is safe for pregnant and breastfeeding women to take melatonin.

Melatonin may cause daytime drowsiness in some older adults. Doctors do recommend it for people with dementia. Often children can overcome sleep issues by sticking to it a consistent bedtime. For children who still have difficulties with sleeping, melatonin does appear to be safe for use in the short term.

Evidence for the efficacy of melatonin in the treatment of primary adult sleep disorders. Sleep Medicine Reviews. Auger RR, et al. Journal of Clinical Sleep Medicine. See also Tips for better sleep 8 ways to improve sleep quality as you age Alzheimer's sleep problems Can psoriasis make it hard to sleep?

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