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How Long Does Melatonin Last?

Mary Lucas, RN

Reviewed by Mary Lucas, RN

Written by Nicholas Gibson

Published 04/09/2022

Updated 04/10/2022

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.

How long does it take for melatonin to work? 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. 

11 Sources

  1. Melatonin: What You Need To Know. (2021, January). Retrieved from
  2. Savage, R.A., Zafar, N., Yohannan, S. & Miller, J.-M. (2021, August 15). Melatonin. StatPearls. Retrieved from
  3. Melatonin. (2021, October 6). Retrieved from
  4. Sleeping Pills. (2021, April 27). Retrieved from
  5. Terzano, M.G., Rossi, M., Palomba, V., Smerieri, A. & Parrino, L. (2003). New drugs for insomnia: comparative tolerability of zopiclone, zolpidem and zaleplon. Drug Safety. 26 (4), 261-82. Retrieved from
  6. Hallare, J. & Gerriets, V. (2021, August 23). Half Life. StatPearls. Retrieved from
  7. Terzano, M.G., Rossi, M., Palomba, V., Smerieri, A. & Parrino, L. (2003). New drugs for insomnia: comparative tolerability of zopiclone, zolpidem and zaleplon. Drug Safety. 26 (4), 261-82. Retrieved from
  8. Hardeland, R. (2009). New approaches in the management of insomnia: weighing the advantages of prolonged-release melatonin and synthetic melatoninergic agonists. Neuropsychiatric Disease and Treatment. 5, 341–354. Retrieved from
  9. Cummings, C. (2012, June-July). Melatonin for the management of sleep disorders in children and adolescents. Paediatrics & Child Health. 17 (6), 331–333. Retrieved from
  10. Zisapel, N. (2018, August). New perspectives on the role of melatonin in human sleep, circadian rhythms and their regulation. British Journal of Pharmacology. 175 (16), 3190–3199. Retrieved from
  11. Tips for Better Sleep. (2016, July 15). Retrieved from
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Hims & Hers has strict sourcing guidelines to ensure our content is accurate and current. We rely on peer-reviewed studies, academic research institutions, and medical associations. We strive to use primary sources and refrain from using tertiary references. See a mistake? Let us know at [email protected]!

This article is for informational purposes only and does not constitute medical advice. The information contained herein is not a substitute for and should never be relied upon for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment. Learn more about our editorial standards here.

Mary Lucas, RN

Mary is an accomplished emergency and trauma RN with more than 10 years of healthcare experience. 

As a data scientist with a Masters degree in Health Informatics and Data Analytics from Boston University, Mary uses healthcare data to inform individual and public health efforts.

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