Is Melatonin Safe? Common And Uncommon Side Effects

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melatonin supplements For those struggling with their sleep cycles, taking oral melatonin* is one of the first ports of call. But in spite of its common usage and over the counter status, there are still a few question marks surrounding its use. As with anything else, taking melatonin as a supplement comes with the potential for side effects. Some of these are well-known and publicized, but other, rarer side effects are more obscure and unknown to the general public. So is melatonin safe to take for sleep?

What Is Melatonin?

Melatonin is a hormone naturally produced in the pineal gland that regulates the body’s biorhythm, or natural sleep cycle. Young people produce a lot of melatonin, and the amount tends to decrease with age. Other factors which can impact melatonin levels are the body’s exposure to natural light, alcohol, caffeine, and blue light (such as computers and phone screens).

The level of melatonin in your system is controlled by your body clock. It rises in the evening, remains at a high level during sleeping hours and then falls again in the morning. There is no recommended dietary allowance (RDA) just yet for melatonin in food, so many food databases don’t include amounts of it. However, research shows it can be found in a variety of foods, including:

  • Fish
  • Grains, such as oats and barley
  • Fruits and vegetables — specifically bananas, tart cherries, pineapple, and goji berries
  • Eggs
  • Nuts — specifically walnuts, almonds, pistachios, and pumpkin seeds

Consuming these foods throughout the day may be enough to naturally improve your sleep cycle, but consistency is important. If you prefer to dose melatonin a little more precisely, it can also be prescribed in pill form by a doctor, or purchased as a natural supplement.

What Is Melatonin Used For?

Melatonin can be used to aid in a wide spectrum of sleep disorders. It’s primarily used to treat insomnia, but can also be useful in helping those suffering from seasonal affective disorder, or winter depression, and those attempting to regulate their circadian cycle. It may also be useful in controlling sleep patterns for shift workers, helping reduce sleep confusion post-surgery or helping people tackle jet lag.

Melatonin is also being studied as a potential treatment in other areas, including as a menopausal aid and as an immune system strengthener. The hormone also has an impact against free radicals, meaning it could possibly have anti-aging benefits, and can be applied to the skin to protect against sunburn (though much more research is needed to confirm any of these effects, as well as any potential side effects).

Melatonin can be prescribed by a doctor, but in the United States it’s also commonly available to purchase over the counter. It’s fairly inexpensive and easy to find, but there are particular question marks concerning its potency and dosage.

How To Take Melatonin

Like other supplements, melatonin is available in multiple forms. It can be taken orally or applied topically, and the proper application or dosage varies depending on the form you choose.

  • Capsules and tablets. This type of melatonin supplement is swallowed with water, and often taken 30 minutes to an hour before bedtime.
  • Liquid and sprays. Liquid melatonin may be quicker to absorb because it works sublingually. It’s generally taken 20 minutes to an hour before bedtime. It’s available in dropper form or as a spray.
  • Gummies. This chewable form of melatonin is a good option for those who have trouble swallowing pills. Most manufacturers recommend melatonin gummies 20 minutes to an hour before bedtime.
  • Creams and lotions. This form of melatonin is applied directly to the skin just before bedtime.

Is Melatonin Safe?

“Melatonin is considered safe for short-term use, with some studies indicating one to three months and others indicating up to six months,” says Dr. Carleara Weiss, PhD, MS, RN, and sleep scientist. Though most medical professionals will only advise using melatonin for a short period of time, there are instances where participants continued to use the hormone for years and reported no concerns or adverse side effects, including a small study that focused on children with neurodevelopmental abnormalities.

Because it’s a naturally occurring hormone in the body, the risk of addiction is generally considered very low, though this can vary from person to person. Melatonin abuse is also far less common than with other prescribed sleeping aids, as there are no immediate feelings of comfort or euphoria.

Proper dosing, however, is key. “When taken at the recommended doses, natural sleep aids are generally considered safe,” says Chelsie Rohrscheib, a neuroscientist and the head sleep expert at Wesper. “It’s also important to note that most supplements in the US are not regulated by the FDA.” Make sure to purchase melatonin supplements from reputable brands that you trust.

Keep in mind that while there is research that shows the use of melatonin may help with several aspects of sleep, more studies are needed to confirm its safety and efficacy for certain populations.

Children and Melatonin

Some research indicates that melatonin can help children who experience sleep problems, which are often found in those with attention deficit hyperactivity disorder or those on the autism spectrum. However, melatonin can lead to bedwetting or agitation in some kids.

Information regarding the safety of melatonin as a sleep aid for children is mixed. While the American Academy of Pediatrics says short-term use is considered relatively safe, it warns that studies regarding long-term use are lacking. That’s why many experts don’t recommend melatonin for children. Overall, if you’re considering giving your child melatonin, be sure to consult with your pediatrician first.

Melatonin Use During Pregnancy

At this time, there just isn’t enough research to determine whether melatonin supplements are safe during pregnancy. If you’re experiencing sleep issues during pregnancy, it’s important to speak with your healthcare provider to discuss your options.

Other Groups

Melatonin may also be contraindicated for people with specific health conditions. “People taking medication such as anticoagulants to treat cardiovascular problems and diabetes should consult their primary care provider before using natural sleep aids because they interfere with these medications,” says Weiss.

What Are Common Side Effects of Melatonin?

As with any synthetic hormone, there are some very common side effects of taking melatonin supplements, though these typically end once it stops being taken. The most reported include:

  • Sleepiness and drowsiness
  • Headaches
  • Stomach cramps
  • Short-term feelings of irritability or depression.

These symptoms can be managed through consistent and fairly low dosage. However, if you’re struggling with drowsiness, sleepiness or dizziness as a side effect, it’s important to avoid driving or operating heavy machinery.

What Are The Uncommon Side Effects of Melatonin?

Melatonin can interfere with other medications, particularly those taken for diabetes and blood pressure, or blood thinning medications such as aspirin. It can increase levels of blood sugar, so those with diabetes must monitor themselves carefully if taking these supplements. Melatonin can also increase immune system function, which can be dangerous for transplant patients, as it increases the body’s likelihood of rejection.

Because it’s a hormone, melatonin could possibly interfere with ovulation.

There are also risks in terms of taking an overly high melatonin dosage. By taking a consistent dosage of melatonin, your body may become reliant on it and stop producing melatonin itself. Thus, it can actually have adverse effects of regulating biorhythm and aiding insomnia, particularly after you stop taking it.

Some other less common side effects of melatonin supplements are vivid dreams, low blood pressure and a slightly lower body temperature.

Melatonin Dosages

Melatonin dosage comes in a wide variety of strengths, from 0.2 mg to 20.0 mg. The most commonly useful dosage falls between 0.3 and 1.0 mg. Typically, if you can find the perfect dosage for you, you can get all the benefits of melatonin whilst still minimizing the side effects.

Just because it’s unregulated and easy to purchase doesn’t mean it can be taken without consequence — it’s worth noting that melatonin is a powerful hormone. Weiss says that like all natural sleep aids, melatonin has side effects and contraindications. Exercising caution when taking melatonin is the best way to get maximum benefits with minimum drawbacks.

Melatonin Overdose

While taking too much melatonin can negate its positive effect, there’s virtually no evidence that overdosing on melatonin could be fatal or even life-threatening.

Melatonin Alternatives

While melatonin is unique because it influences the circadian rhythm, there are other natural sleep aids that can promote relaxation and help calm anxiety. That might be all you need to nod off.

  • Ashwagandha. This herb may be sufficient if you’re looking to fall asleep faster and stay asleep longer. However, “The effect of ashwagandha on sleep is mild,” says Rohrscheib. “Unfortunately, it’s not likely to help with chronic sleep issues such as anxiety, but it can be used by individuals that have occasional sleep problems.” She says ashwagandha is not comparable to melatonin because they work differently in the brain. “While ashwagandha promotes relaxation, melatonin acts as a circadian rhythm regulating hormone that our brain makes naturally. Melatonin should be reserved to help you adjust your sleep, whereas ashwagandha is better for individuals who find it difficult to wind down at night.”
  • Magnesium. This essential mineral helps promote muscle relaxation and has an effect on specific brain activity that helps us sleep. “Because of this, research has suggested that magnesium may help improve sleep quality, reduce insomnia, and increase sleep time in people with some sleep disorders,” says Susan Schachter, MSRDN.
  • Chamomile, valerian root, and lavender. Weiss says these herbs have the most studies testing their efficacy for improving sleep. “However, even for those herbs, the science is inconsistent. Most of the recommendations are based on peoples’ experiences and cultural influence,” she says.

Is Melatonin Worth The Risk?

Melatonin is a powerful hormone, and works unlike other sleep aids and natural remedies. It’s a sleep regulator, rather than a sleep initiator. Those who are really struggling with insomnia may feel compelled to take a high dose, thinking it’ll have a stronger effect. However, at the wrong dose, melatonin can actually make the sleeping cycle much worse, inducing drowsiness and preventing the body self-regulating its natural sleep cycle.

Used appropriately, however, melatonin can be helpful as a short-term sleep aid. Speak with your healthcare provider for specifics about dosing and form.

The Last Word From Sleepopolis

If you’re struggling to sleep, it’s normal to look for remedies. For many people, melatonin can be a safe and effective short-term solution. However, we don’t yet have the research to confirm its safety for all populations, including children or those who are pregnant. If you’re experiencing sleep issues and you’re considering melatonin, speak with your healthcare provider first, and make sure to ask for specific recommendations about the best form and dosage for you.

*Restrictions and regulations on supplements may vary by location. If you ever have any questions or concerns about a product you’re using, contact your doctor.

Jessica Timmons

Jessica Timmons

Jessica Timmons has been working as a freelance writer since 2007, covering everything from pregnancy and parenting to cannabis, fitness, home decor, and much more. Her work has appeared in Healthline, mindbodygreen, Everyday Health, Pregnancy & Newborn, and other outlets. She loves weight lifting, a good cup of tea, and family time. You can connect with her on her website, Instagram, and LinkedIn.