Do not use melatonin if you are pregnant or breastfeeding or have an autoimmune disorder, a seizure disorder or depression. Talk to your health care provider if you have diabetes or high blood pressure.
If you've been drinking alcohol, it's also not safe to take melatonin. Melatonin is also not for you if you're pregnant or breastfeeding. Researchers simply don't have enough data to know if it's safe for fetuses or breastfed babies.
In general, melatonin should not be given to healthy, typically developing children under age 3, as difficulties falling and staying asleep in these children are almost always behavioral in nature.
Melatonin has been linked to headache, dizziness, nausea, stomach cramps, drowsiness, confusion or disorientation, irritability and mild anxiety, depression and tremors, as well as abnormally low blood pressure. It can also interact with common medications and trigger allergies.
Some medicines and melatonin can affect each other and increase your risk of side effects. Lots of medicines may increase or decrease the drowsy-making (sedating) effects of melatonin.
Furthermore melatonin has been shown to have valuable effects on cardiovascular health, blood pressure, and endothelial function and it might benefit patients with heart failure.
- In the UK, the Medicines Control Agency has banned the high-street sale of melatonin after it was decided the compound was "medicinal by function," and as such requires a drug license. The MCA has written to all relevant suppliers, which comprise mainly health food shops, ordering them to stop selling the product.
Melatonin is generally safe for short-term use. Unlike with many sleep medications, with melatonin you are unlikely to become dependent on it, have less response to it after repeated use or experience a hangover effect. The most common melatonin side effects include: Headache.
"By adding extra melatonin every night, you might throw off that delicate balance in the long run, and might experience the side effects of the body needing to re-balance, whenever you decide to stop using melatonin," says Dr. Raymann.
In the UK and most of Europe, it's classed as a medicine, not a health supplement and as such, requires a prescription. This is because melatonin is considered “medical by function” which means that it requires a drug licence.
Less common melatonin side effects might include short-lasting feelings of depression, mild tremor, mild anxiety, abdominal cramps, irritability, reduced alertness, confusion or disorientation.
How Long Does Melatonin Stay in Your System? The half-life of melatonin is between 20 and 50 minutes, meaning half of the initial dosage in the body is eliminated after that amount of time. In total, melatonin stays in your system for about four to five hours.
In several clinical trials, melatonin was found to be well tolerated and not associated with serum enzyme elevations or evidence of liver injury. Despite wide scale use, melatonin has not been convincingly linked to instances of clinically apparent liver injury.
Melatonin is generally regarded as safe for seniors by physicians and pharmacists because its side effects are mild, it's not habit forming, and it does not cause withdrawal symptoms if you stop taking it suddenly.
French authorities are urging certain populations to avoid consuming food supplements containing melatonin after incidences of adverse effects were reported to the country's nutrivigilance scheme.
If your levels are too high (for example, if you have recently got off a long-haul flight), you can go out into the light in the morning and do some exercise in the evening. Melatonin pills are available in Australia. Currently, you need a prescription from your doctor for melatonin.
OTC melatonin has been banned for years in the United Kingdom (UK), European Union, Japan, Australia and most recently Canada. Exogenous melatonin is not outlawed by these countries but regarded as a medicine, available only by prescription.
Melatonin's target sites are both central and peripheral. Binding sites have been found in many areas of the brain, including the pars tuberalis and hypothalamus, but also in the cells of the immune system, gonads, kidney, and the cardiovascular system (39, 40).
High blood pressure: Melatonin can raise blood pressure in people who are taking certain medications to control blood pressure. Avoid using it. Seizure disorders: Using melatonin might increase the risk of having a seizure.
Melatonin inhibits angiotensin II–induced atrial fibrillation through preventing degradation of Ang II Type I Receptor–Associated Protein (ATRAP)
Sleep Medications Containing Melatonin can Potentially Induce Ventricular Arrhythmias in Structurally Normal Hearts: A 2-Patient Report - PMC.