When we’re having trouble sleeping, we want a quick fix. Thanks to the easy over-the-counter availability of melatonin, many people turn to this supplement for insomnia and jet lag. But is it really a magic pill? Are there side effects to melatonin use?
We turned to our resident expert, Pamela Swift, PhD, a clinical psychologist for the Sleep Program at The University of Vermont Medical Center. She’s one of just 200 board-certified sleep specialists in the country, and prior to coming on board with the Sleep Program, she practiced in the child psychiatry department for several years.
Here, she answers common questions about the sleep aid.
10 FAQs About Melatonin
1. How does melatonin work?
Before melatonin ever came in a bottle, it was (and still is) a hormone that’s made naturally by the body. “When we’re exposed to light -- from sunlight, artificial light or even screens -- that tells our body it’s daylight, and our brain suppresses melatonin production to increase alertness,” Swift explains. “But when those light sources decrease, our pineal gland gets a signal from the hypothalamus to ramp up melatonin production, and we start to feel sleepy.” This process typically happens over the course of three to seven hours.
2. Is melatonin safe?
Melatonin is largely viewed as safe, Swift says, “and we are relatively confident melatonin isn’t habit-forming like some other sleep aids.”
But, she says, it’s also important to remember that we don’t really know its ramifications at high doses and over long-term usage. “There’s just not enough research yet to give us solid data on the potential long-term risks of melatonin,” Swift says.
That’s especially important when we think about giving melatonin to kids and adolescents, Swift warns. She notes that in many other countries, it's only available by prescription.
"Research has shown that there has been a huge rise over the past 10 years in accidental melatonin ingestions and calls to Poison Control,” Swift says. “This increase seems to be impacted heavily by children under 5 accessing and taking too much. You need to treat this as any other medication and keep it secured and away from children.”
3. Should I try a melatonin supplement to help with sleep?
Melatonin is inexpensive and readily available, and generally safe, so it makes sense that people want to give it a shot, Swift acknowledges. However, it has a pretty limited benefit.
“Melatonin is marketed like a sedative,” she says, meaning that manufacturers imply that if you take it, you’ll feel sleepy and fall asleep and sleep well. But, she says, in the body, it’s really just a hormone that tells your body the time (i.e., “it’s about 9 pm and time to wind down”); it doesn’t actually make you sleepy directly. So while increasing melatonin production eventually leads to sleep after several hours, the evidence is mixed that a dose of it – in the form of a supplement – will make you fall asleep quickly.”
For those who feel sleepy but have insomnia, which is trouble falling asleep, staying asleep, or sleeping until your alarm, melatonin is usually not helpful, Swift says. For those who have other sleep disorders that are more related to timing, such as circadian rhythm disorders, melatonin can make a difference.
4. Is it important to figure out why I’m having trouble sleeping?
“Big time,” says Swift. “The ‘why’ is so important, because there are a lot of possible reasons someone might have trouble sleeping.” Life transitions, such as aging, pregnancy or postpartum, or adjusting to life as a new parent or caregiver, can also interfere with sleep, as can chronic medical conditions or medications.
“Having a mental health background, I notice that a lot of the drivers are behavioral, and can be related to anxiety, depression or low mood,” says Swift – and for these causes, cognitive behavioral therapy for insomnia (CBT-I) is the best prescription. “It’s a long-term solution, it’s not another medication.
The trouble is that there are not enough providers doing this work, so you may need to seek support from other sources in the meantime. Some reputable internet sources include the American Academy of Sleep Medicine or Society for Behavioral Sleep Medicine, as well as coaching apps like CBT-I Coach or Insomnia Coach,” she says.
If you’re concerned about your poor sleep and considering taking melatonin, you should have a discussion with your primary care provider. “One, they know you the best, and two, you may be able to see them sooner than a behavioral sleep medicine provider,” Swift says. “They’re the perfect place to start.”
5. Can melatonin help me with jet lag, or adjust to shift work schedule changes?
According to Swift, the short answer is “potentially, but it is complicated.” When it comes to jet lag, it’s best to get outside in bright light if you arrive at your destination in the daytime and get your day going, even if you feel sleepy. “That will help you the most,” says Swift. “You’ll get on their time zone much faster if you get there and live your life at their time. This may mean a wonky night or two of sleep, but it is more reliable than trying to fiddle with melatonin for timing.”
As for shift work, Swift and her team have helped plenty of people adjust when switching back and forth between day and night work schedules. “You can adjust your sleep rhythm with bright light and darkness and build in transition days. Those things are often more helpful than melatonin.”
6. Who could benefit most from melatonin?
“Melatonin can be helpful for folks who have what’s called delayed sleep phase syndrome, which is the timing condition I mentioned earlier,” says Swift. While people with delayed sleep phase syndrome are capable of falling asleep, the problem is that they don’t feel sleepy at the time they need to go to bed. “They may not fall asleep until 2 am, and then they have to get up at 6 am, so they’re chronically sleep deprived,” says Swift.
Kids and adolescents with neurodivergence, like autism spectrum disorder and ADHD, who struggle with sleep may also benefit from a low-dose supplement. As Swift explains, some evidence suggests there may be some anomalies in the way their bodies produce and maintain melatonin. Parents who are interested in trying melatonin for their neurodivergent children should definitely seek out the support and guidance of a pediatrician, behavioral specialist or sleep center provider, Swift advises.
And finally, says Swift, “there is also a potential benefit for older adults, as we make less and less melatonin as we age. However, this can be tricky: While there’s not enough data to say, ‘everyone over 65 should use melatonin,’ it may be worth a try for some after a conversation with their prescribing providers,” she says.
7. Who should not take melatonin?
Swift says she would not recommend it for people who tend to have vivid dreams and nightmares. Melatonin can cause individuals to go into REM sleep more reliably or for longer periods, and this is where remembered dreaming happens. “Melatonin can make those dreams more intense,” she warns.
There are also some medications that can be contraindicated with melatonin. “Some of those medications change the way your body metabolizes melatonin and end up forcing the melatonin to stay in your body much longer than desired,” Swift explains. “The side effects aren’t extreme, but they can be uncomfortable. Check with your prescriber first.”
8. What do you recommend for melatonin dosage and timing?
“Always discuss adding any supplements to your regimen with your prescribing provider and primary care provider. If melatonin is reasonable given your symptoms, Swift suggests starting out with the lowest dose you can find, or getting it prescribed. “For children and adolescents, you’ll want to look for a 0.5-mg dose since that is likely the smallest version you can find over the counter. Start with just one tablet or gummy, and monitor response,” she says.
Adults may start somewhere closer to 3mg, Swift says, but she encourages using the kids’ version first.
As for timing, it’s different for different people. But a good starting point is taking the supplement around three to five hours before your desired bedtime.
9. Are there any melatonin side effects?
Side effects are usually mild, but they can be unpleasant: mostly morning grogginess, headaches and nausea. These feelings usually indicate you’ve taken too high a dose, that you need to adjust your timing, or that it may not actually be for you. Keep an eye on your dream content as well. If it is hedging towards the unpleasant or scary, melatonin may be to blame.
10. Is there a melatonin brand I should look for?
What’s most important is to look for a brand that’s certified, Swift stresses. Many supplements are not fully regulated by the Food and Drug Administration, but there are other third-party organizations – USP (United States Pharmacopeia) or NSF (National Sanitation Foundation) being two that are key – that offer independent verification that the actual ingredients and the dosage match what’s on the label.
“In 2022, we actually received an alert from the American Academy of Sleep Medicine (AASM) about ingredient discrepancies in melatonin supplements,” says Swift. “The AASM found that actual dosages ranged from about 80% less than what was indicated, to as much as nearly 500% more.” These supplements can also be adulterated with other products, including serotonin and CBD. Certification is not foolproof, but it can give you some piece of mind that you are seeking out more rigorously reviewed products.”