Can You Overdose on Melatonin?
Learn if it's possible to overdose on melatonin supplements and what the correct dosage of this sleep aid is.
Jun 9th, 2022 •
Expert Insights from Dr. Luis Javier Peña-Hernández, MD, FCCP, a lung health specialist at PCSI, the largest integrated pulmonary and chest specialty group in Palm Beach County.
People who experience sleep problems often turn to some form of aid for help. Melatonin supplements are a popular choice since they are sold over-the-counter and marketed as a natural way to help you get better sleep.
“Many people turn to melatonin as an over-the-counter solution to their sleep problems. Although it is available as an OTC medication, it is wise for people to consult with their doctor before taking melatonin. Your doctor can help you understand dosage guidelines and avoid adverse effects from other medications you’re taking,” says Dr. Peña-Hernández.
But just because the body naturally produces melatonin anyways doesn’t necessarily mean it’s safe to administer at your own will. In this article, we’ll review how melatonin works and the potential dangers of overdosing on melatonin.
Melatonin is a hormone that is naturally produced in our bodies by the pineal gland in the brain. Melatonin production is regulated by exposure to light sources—it is secreted when the sun goes down and causes the feeling of sleepiness. This is how melatonin helps regulate our circadian rhythms otherwise known as our natural body clock.
Melatonin is responsible for maintaining normal sleep-wake cycles in humans. Melatonin levels rise during the night—allowing us to fall asleep. These increased levels of melatonin remain throughout the night to keep you asleep, then drop in the morning with the rising of the sun so that you wake up.
While this hormone is produced naturally in our bodies, melatonin can also be found in small doses in some fruits and vegetables. Aside from this, it’s also available in a dietary supplement form.
Why Do People Take Melatonin Supplements?
Melatonin available in supplement form is made synthetically in a lab and sold as holistic medicine. It can be taken as a pill or quick dissolve tablet, and is used to treat a variety of sleep disorders such as jet lag, shift work sleep disorder, and sleep deprivation.
Melatonin supplements may also be used to treat insomnia related to traumatic brain injuries, ADHD, and sleep issues in children with autism, cerebral palsy, and other developmental disabilities.
Some people even use melatonin supplements to help improve sleep after stopping benzodiazepine use and smoking cigarettes. Some find relief using melatonin supplements when suffering from Alzheimer’s disease, bipolar disorder, chronic obstructive pulmonary disease, and insomnia caused by beta-blocking medications.
While it’s important to always consult with your doctor before taking any new supplements, melatonin can generally be taken by those who have high blood pressure, Seasonal Affective Disorder (SAD), chronic fatigue, migraines, and a variety of other health conditions. Sometimes cancer patients use melatonin to help prevent some of the side effects of chemotherapy.
The correct dosage of melatonin relies greatly on the age of the person taking it, how healthy they are, and the reason they are taking it. If melatonin is being used to treat insomnia, jet lag, or to adjust a circadian rhythm, the standard dose ranges from 0.3 milligrams up to 5 milligrams.
Since melatonin supplements are not regulated by the Food and Drug Administration (FDA), supplements have various dosages per pill. Sometimes they can have ten times the recommended dose in one pill.
It is also difficult to determine if the amount of melatonin per dose advertised on a bottle is truly what is being ingested since it’s not regulated by the FDA. One study examined the actual dosage of 31 different melatonin supplements and found that 70% of them contained either more or less melatonin than what was advertised. They even found variability in melatonin amounts between lots of the same product—the worst case had variation by as much as 465%.
This can be a bit scary, especially if using melatonin for a child. If you are concerned about overdosing on melatonin, it’s recommended that you purchase pharmaceutical-grade melatonin online as the dosage is more likely to be reliable. It’s also recommended that first-time melatonin users take the lowest dose possible, and work their way up to the correct dosage in 0.5-milligram increments.
When it comes to the question concerning whether or not you can overdose on melatonin, the answer is yes and no. There has never been a case reported of anyone dying from too much melatonin, or even becoming seriously ill, so no, you cannot really overdose in the fatal sense.
On the other hand, you can certainly take too much melatonin, which can produce adverse side-effects you likely want to avoid. If you are worried about whether or not you have taken too much melatonin, take a look at the warning signs and symptoms of taking larger doses of melatonin than recommended and adjust your intake accordingly.
“Taking too much melatonin can lead to adverse effects such as headaches, depression, anxiety, pain, irritability, and grogginess,” says Dr. Peña-Hernández.
Signs of Melatonin Overdose
Common side effects of melatonin overdoses include:
- Daytime grogginess
- Stomach cramps
- Joint pain
- Low body temperature
Taking too much melatonin can have a wide range of harmful effects. Melatonin overdoses can lower the sperm count and libido of men, and affect estrogen and progesterone hormone levels in women. Some also suggest that melatonin can affect the ovulation and menstrual cycles for women as well.
Taking too much melatonin can cause a person to be more awake than they would be normally—producing the opposite effect of what was originally intended (if taking it as a sleep aid). Excess melatonin may also cause a person to feel incredibly tired during times that they wish to be awake, and may cause intense dreams and/or nightmares.
“Long-term melatonin overdose can cause hormonal imbalances in the body, especially as it relates to women’s levels of estrogen and progesterone,” says Dr. Peña-Hernández.
Melatonin is relatively safe, but there are some dangers associated with taking too much. Depending on the severity of symptoms, a person may need to call 911 if they’ve taken large amounts of melatonin and are experiencing chest pain, extremely high blood pressure, or shortness of breath.
A melatonin overdose can typically be waited out, or one may find relief from calling their doctor to seek medical advice. If a person is taking other medications, it’s most certainly important to speak with a doctor.
In fact, it’s recommended that you speak with a doctor before taking a melatonin supplement to avoid any unpleasant drug interactions. It’s also recommended that pregnant women discuss the use of melatonin with their doctors before taking it.
The good news is that the effects of melatonin are short-term, and there should be no long-term side effects that result from taking too much. But still, we are not doctors and the only medical advice we can offer is to content licensed healthcare professionals when you are concerned about your health, well-being, and safety.
Melatonin can react negatively with other medications, so it’s imperative to speak with a doctor before taking melatonin if you are on any sort of prescription medication. The main drugs that melatonin interacts negatively with are sedatives (CNS depressants), blood thinners anticoagulants, birth control pills (contraceptives), steroids, diabetes medications, and immunosuppressants.
Blood-thinning medications (anticoagulants) can be dangerous when paired with melatonin as it has a chance of increasing the risk of bleeding. Melatonin can also make blood pressure and diabetes medications less effective. Melatonin may also make steroids and immunosuppressant drugs less effective, and so it is not recommended that melatonin be taken when on these medications.
Women who are taking birth control pills may not benefit from taking melatonin, as many of these hormonal contraceptives already increase the body’s natural melatonin levels, and so taking a supplement may cause excessive drowsiness.
Other medications, such as those that prevent seizures (anticonvulsants) may also become less effective when taking melatonin. If a person with epilepsy who is on medication to treat it decides to take melatonin, it could actually increase the risk of having a seizure.
If you’re considering giving melatonin to a child, it’s best to speak to a doctor ahead of time to rule out any unwanted side effects or drug interactions that may occur. Melatonin is relatively safe for children so long as the dose is appropriate.
However, the risks of a melatonin overdose are more severe for children, so should a child experience some of the more intense side effects of too much melatonin, medical attention should be sought immediately. It’s also not recommended to give melatonin to a child whose sleep issues are situational.
A trip to the pediatrician is a good idea when your child is having any sort of trouble sleeping in order to rule out any medical conditions, such as an ear infection. It may also help to examine your child’s bedtime habits.
Some studies have suggested that using melatonin during childhood may delay the onset of puberty. These studies have only been conducted on animals thus far, and there is yet to be substantial proof showing this is the case for children. However, you can never be too safe.
As previously stated, melatonin can be found naturally in a variety of fruits, vegetables, nuts, and grains. Such natural sources of melatonin include:
- Tart cherries
- Rolled oats
- Sunflower seeds
- Mustard seed
- Red wine
Sourcing your melatonin naturally through the foods you eat may be a safer alternative to unregulated supplements.
Because melatonin supplements are not regulated by the FDA and there are no strict guidelines on dosage, taking melatonin can be dangerous. Melatonin can also have adverse interactions with a wide range of medications. Although melatonin is an over-the-counter drug, it’s best to speak with your doctor before taking it to rule out any dangers.
If you have taken too much melatonin, you may notice signs such as excessive daytime grogginess, headaches, dizziness, or mood problems. Anytime you experience adverse reactions to a medication, it’s important to promptly consult with a healthcare professional.
For safer alternatives to melatonin supplements, you can source your melatonin through fruits, vegetables, nuts, and grains. You may also be interested in other sleep remedies such as taking a warm bath or using essential oils. If sleep problems persist, speaking with a sleep specialist may help you get to the root of your problems.
It may also be a good time to start considering investing in a new mattress and pillow suited for your own unique sleep preferences and support needs. You can start by taking our mattress quiz to find out the best type of mattress for you, and check out our mattress buying guides to learn more about the best mattresses on the market today that fit your desired firmness, support, and more.
Dr. Luis Javier Peña-Hernández, MD, FCCP, is a lung health specialist at PCSI, the largest integrated pulmonary and chest specialty group in Palm Beach County. His areas of expertise include asthma and immunotherapy, COPD, lung cancer, and invasive diagnostic techniques in pulmonary medicine including endo-bronchial ultrasound and diagnostic bronchoscopy. He is also one of the few experts in cardiopulmonary exercise testing and exercise physiology in Palm Beach County.
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