NSAIDs such as ibuprofen (Advil, Motrin) may lower levels of melatonin in the blood. Steroids and immunosuppressant medications. Melatonin may cause these medication to lose their effectiveness. DO NOT take melatonin with corticosteroids or other medications used to suppress the immune system.
"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.
Less common melatonin side effects might include short-lasting feelings of depression, mild tremor, mild anxiety, abdominal cramps, irritability, reduced alertness, confusion or disorientation. Because melatonin can cause daytime drowsiness, don't drive or use machinery within five hours of taking the supplement.
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.
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.
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.
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).
Most people overdo it with melatonin by taking upward of 10 milligrams or more prior to bed and then claim it doesn't work. Taking too much melatonin can actually cause rebound insomnia —either rendering the supplement ineffective or worse, exacerbating your already sleepless nights further.
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.
Melatonin takes between four to eight hours to wear off, but the amount of melatonin you take can cause this number to vary significantly. Generally, Buenaver suggests taking the lowest dose possible and advises starting at around one to three milligrams.
Melatonin is generally considered safe to take every night at doses between 0.5 mg and 5 mg. A safe starting dose of melatonin is between 1 mg and 5 mg for adults. More melatonin can cause side effects, particularly in older adults. For older adults, lower doses, such as 1 mg, are usually considered enough melatonin.
Melatonin might lower blood pressure. Taking melatonin along with medications that lower blood pressure might cause blood pressure to go too low. Monitor your blood pressure closely.
Either way, melatonin can help you move the timing of your circadian rhythm earlier, helping you fall asleep at an earlier time and shift your schedule forward. Take melatonin a few hours before bedtime to give it enough time to work. Four to eight hours before your DLMO will make you feel sleepy earlier than usual.
With less than six hours of sleep, the additional melatonin may leave you groggier than usual and tired the next day. Therefore, you do not want to take melatonin in the morning or when you won't be able to sleep long enough.
Daytime sleepiness or grogginess
The popular use of melatonin is to make you sleep. However, this sleepiness can carry on into the following day. Daytime sleepiness is when you feel the need to fall asleep despite wanting to be awake. This is the most common side effect people experience when taking melatonin.
If you plan on using melatonin to help you sleep, it's best to take it two or three hours before your bedtime. On the flip side, if you find yourself unable to sleep in the middle of the night, keep in mind that popping a melatonin at midnight won't necessarily have immediate results.
There is no evidence that you can become physically dependent on the supplement, and you typically won't develop withdrawal symptoms if you stop taking it. But if you've become convinced that taking melatonin is crucial for sleep, experts say, you still may struggle to kick the habit.
Melatonin promotes calmness and relaxation, helping individuals rest their bodies and minds in order to fall asleep. While most people take melatonin to help with sleep, others may take the supplement for their moods. By nightfall, your body starts to naturally produce melatonin to get you ready to rest.
A 2017 study indicated melatonin as an effective and safe option for treating people with anxiety following acute coronary syndrome (ACS). A 2018 study found that the administration of melatonin was more effective in improving anxiety and sleeping patterns than the drug oxazepam in people undergoing heart surgery.
Melatonin may be helpful if you're experiencing anxiety related to or co-occurring with insomnia, but it's not generally recommended as a treatment for anxiety. Rather than trying to manage a possible anxiety disorder with an over-the-counter dietary supplement, we suggest you talk with a medical professional.
Melatonin does tend to have less risky potential side effects than certain prescription sleep aids, Grandner says, but he adds that “melatonin is not a good alternative to prescription sleep medications. It does not work as a sedative and it is ineffective in most cases of insomnia.”
The interaction of melatonin and caffeine also stimulated tryptophan metabolism and thereby preventing vitamin B6 deficiency, anemia, negative nitrogen balance, tissue wasting, and accumulation of xanthurenic acid, thereby promoting sleep.