Medically reviewed by Mary Lucas, RN
Written by Our Editorial Team
Last updated 4/10/2022
If you occasionally find it hard to fall asleep, work a late shift or travel often and switch back and forth between time zones, you may have looked into sleep aids such as melatonin.
Melatonin is a hormone that’s released by your brain. It helps control your circadian rhythm — the natural, 24-hour cycle of certain activities within your body — and plays a role in helping you to fall asleep.
You can find synthetic melatonin in natural supplements for improving sleep, including our Sleep Gummy Vitamins.
Since no one wants to wake up feeling sleepy, one of the most common questions about sleep aids like melatonin is how long they last. The good news with melatonin is that it doesn’t last for very long — in fact, a normal dose of melatonin is usually out of your body within a few hours.
Below, we’ve explained exactly what melatonin is, as well as how it works as a popular remedy for sleep issues such as insomnia, jet lag and delayed sleep phase syndrome.
We’ve also explained why melatonin’s short half-life means it won’t stay in your system for long, as well as what this means if you’d like to use melatonin for sleep as effectively as possible.
Melatonin is a naturally-occurring hormone that’s produced in your pineal gland — a pea-shaped gland inside your brain. It plays an important role in regulating your sleep-wake cycle, a natural process that your body uses to help you stay alert during the daytime and sleepy at night.
Your pineal gland releases melatonin in response to darkness, which is part of what causes you to feel tired and ready to sleep in the evening and nighttime. Light suppresses the production of melatonin, causing you to feel alert and awake.
Since melatonin signals to the body that it’s time to go to sleep, many people with sleep issues find that melatonin supplements help them sleep better.
Melatonin is widely available as a dietary supplement. Melatonin supplements usually contain a synthetic form of melatonin that works the same as the melatonin produced by your body.
Because of the effects of melatonin on sleep, it’s often used to treat insomnia and other sleeping disorders. Common uses for melatonin include:
Treating delayed sleep phase syndrome (difficulty sleeping at a normal time)
Correcting a non-24-hour sleep-wake disorder
Treating insomnia (difficulty falling asleep or staying asleep)
Resetting your internal clock while traveling to a new time zone
Adjusting to a new sleep cycle due to night shifts or other shift work
Treating certain sleep disorders that affect children
Melatonin sleep supplements are also used to treat other health issues, such as hypertension (high blood pressure), migraines, thrombocytopenia (low blood platelet counts), and to reduce the severity of sunburn.
It’s worth noting that as a dietary supplement, melatonin is not officially FDA-approved to treat any disease or medical condition as the FDA does not review or regulate nutritional supplements. However, some medications that target melatonin receptors are approved by the FDA to treat insomnia.
One of the most common worries many people have about using sleep aids is the possibility of waking up the next morning feeling tired.
This is a realistic concern, especially with prescription sleeping drugs. In fact, according to the Cleveland Clinic, eight out of every 10 people who use sleep medications like antidepressants, benzodiazepines and Z-drugs experience a next-morning “hangover” effect.
These next-morning hangover effects can occur because many prescription sleep medications have long half-lives, meaning they’re slow to be processed, absorbed and eliminated by your body.
For example, zolpidem (commonly sold as Ambien®) has a half-life of approximately 2.4 hours, meaning it can take nine to 12 hours (approximately four to five half-lives) for the medication to reach a concentration that’s low enough to be considered “eliminated” from your body.
Many benzodiazepines have even longer half-lives, meaning their effects may continue for long after you wake up in the morning.
One significant benefit of melatonin is that it has a much shorter half-life than most prescription sleeping pills. In fact, the half-life of melatonin is generally considered to be between 20 and 45 minutes.
This means that a typical dose of melatonin will take, at most, about four hours to reach a level where it’s no longer active in your system.
During this period, your melatonin levels will decline as the supplement is metabolized by your body. This means that you’re very unlikely to wake up with daytime drowsiness or feeling as if you didn’t get enough restful sleep after using a melatonin supplement.
Melatonin’s short half-life is both a blessing and a curse. Because it works quickly and doesn’t stick around for too long in your body, it’s great for preparing your body for sleep and assisting with issues such as delayed sleep onset.
It’s also a useful supplement for those nights of occasional sleeplessness, where you may just need a little extra help falling into your normal sleep schedule.
However, because melatonin wears off quite quickly, it’s important to time your bedtime dose of melatonin so that it kicks in just before you plan to go to bed.
To counter melatonin’s short half-life, some supplement brands sell extended-release melatonin pills that are absorbed more slowly by your body. These give you a longer window in which you can take melatonin before going to bed.
Although there’s no exact time to take melatonin before sleep, taking it 30 minutes to two hours before your ideal bedtime is a common approach. This approach keeps levels of melatonin high right when you get into bed, which is when it’s needed most as a sleep hormone.
To get the best results from melatonin, try to combine the effects of a melatonin supplement with your body’s natural melatonin production by practicing good sleep hygiene. This means:
Switching off bright lights and keeping your home dim before your bedtime to trigger the natural release of melatonin and increase your natural melatonin levels.
Maintaining a consistent bedtime to keep your body clock functioning properly and make falling asleep easier.
Turning off electronic devices before you sleep to lower your artificial light exposure and avoid developing anxiety at night.
Limiting your afternoon and evening consumption of stimulants that may make it harder to fall asleep, such as caffeine.
Melatonin lasts for about four hours before it’s 95 percent absorbed by your body, meaning you’ll want to take your melatonin supplement 30 minutes to two hours before you plan to sleep for the best results.
Try to avoid taking melatonin more than two hours before your bedtime, as it might start to wear off before you make it to bed.
We offer melatonin as an active ingredient in our Sleep Gummy Vitamins, which are formulated using L-theanine and other evidence-based supporting ingredients to help you feel relaxed and totally ready for sleep in any environment.
We also offer a range of other specialty supplements and vitamins for men for improving focus, immunity and skin, nail, bone and joint health.
Interested in learning more about enhancing your sleep? You can do a quick insomnia test and read our list of science-based ways to fall asleep faster shares techniques that you can use to help deal with primary sleep disorders and enjoy refreshing, uninterrupted sleep every night.