Key takeaways

  • Melatonin, a hormone your body makes naturally, works with your circadian rhythm to signal when it’s time to sleep.
  • Taking melatonin before bed may help you fall asleep faster and increase total sleep time, but it’s not right for everyone. It may cause side effects and interact with certain medications.
  • It’s best to talk with a healthcare professional to determine whether melatonin is right for you.

Melatonin is a hormone that your body makes naturally. It’s often called the sleep hormone, as high levels can help you fall asleep.

However, melatonin lets your body know that it’s time for bed and can make you feel sleepy.

This article is Day 8 of Healthline’s 3 Weeks to Better Sleep Challenge. Follow along to discover small, meaningful habits to help you sleep better, feel more rested, and wake ready to thrive each day.

Missed a day? Catch up with Day 7: Meditation for Sleep, or continue on to Day 9: Foods and Drinks to Have Before Bed.

Melatonin works with your body’s circadian rhythm. It lets you know when it’s time to sleep, wake up, and more.

Melatonin also influences:

Because melatonin helps your body prepare for sleep, people whose bodies don’t make enough of it at night can have trouble falling asleep.

Many factors may disrupt melatonin levels, such as:

  • alcohol consumption
  • smoking
  • caffeine consumption
  • vigorous physical activity
  • certain medications
  • blue light exposure
  • shift work

Taking a melatonin supplement may help counter low levels and regulate your internal clock.

However, it’s important to speak with a healthcare professional, such as a primary care doctor or sleep specialist, to determine if taking melatonin is the best option for you.

A 2019 review of 7 studies found that, compared with a placebo, melatonin may help decrease sleep latency (the time it takes to fall asleep) and increase total sleep time.

Another 2021 review of 23 trials also found that melatonin may positively affect sleep quality in people with certain diseases, including those with primary sleep disorders (disorders that develop independent of another condition).

Additionally, melatonin may counteract jet lag by helping to shift your circadian rhythm to align with the time change. A small 2021 study in people working night shifts also found that, compared with a placebo, taking 3 milligrams (mg) of melatonin on nights when the participants didn’t work helped reduce their circadian misalignment.

Before using melatonin, though, try implementing certain sleep habits, such as:

  • establishing a consistent sleep schedule
  • limiting alcohol and caffeine consumption
  • refraining from using electronic devices before bed

In addition to improving sleep, melatonin may help manage other health conditions, including:

  • Eye health: Though more evidence is needed, a 2019 research review suggests that melatonin supplements may protect eye tissues by reducing free radicals and lowering inflammation.
  • GERD: A small 2023 trial found that taking melatonin in addition to omeprazole may help reduce symptoms like heartburn and pain in people with gastroesophageal reflux disease (GERD). Further studies are needed to confirm these effects.
  • Brain health: Melatonin may counteract some of the brain changes associated with Alzheimer’s disease (AD) and may help improve cognitive function in people with mild AD. However, more research is needed to understand melatonin’s effect on the brain.

If you’re considering trying melatonin for sleep issues, start with a low dose supplement.

For instance, start with 0.5 to 1 milligrams (mg) 30 minutes before going to bed. If that doesn’t seem to help you fall asleep, try increasing your dose to 3 to 5 mg. You could also try taking melatonin earlier — some evidence suggests that it might be more effective when taken a few hours before going to bed.

Medical Perspective

“Melatonin’s sleep benefits appear to peak at about 4 mg, and taking more than 4 to 5 mg is unlikely to provide additional benefit. If it is not working, adjusting when it is taken may be more helpful than increasing the dose.”

— Andrew Perugini, PharmD

Quotes represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.

The goal is to find the lowest dose that helps you sleep.

It’s important to note that the Food and Drug Administration (FDA) doesn’t regulate supplements, and the actual melatonin content in supplements may vary widely. It’s best to find supplements that have been approved by independent third agencies, such as the United States Pharmacopeia (USP), to ensure more accurate dosages and higher quality.

Once your doctor has approved melatonin use and you’ve found a reputable supplement, it’s best to follow the instructions on the supplement packaging, or — if they differ — your doctor’s instructions.

Melatonin supplements are typically considered safe, nontoxic, and not addictive for healthy people, though higher doses and extended release formulations may be more likely to cause side effects.

Temporary side effects may include:

  • daytime sleepiness
  • headache
  • dizziness
  • low body temperature
  • agitation
  • fatigue
  • heart palpitations

Melatonin may interact with a variety of medications by either altering their effectiveness or increasing the risk of side effects.

Medications that melatonin may interact with include:

If you take any of the above medications or any other medications or supplements, talk with your doctor before starting melatonin.

Melatonin may also interact with alcohol.

During pregnancy, melatonin transfers to your developing baby and contributes to the development of circadian rhythms and both the nervous and endocrine systems.

However, few studies have examined melatonin supplementation during pregnancy, so taking melatonin supplements during pregnancy is not recommended.

Additionally, no data exists on the safety of melatonin supplementation while nursing. For this reason, taking melatonin supplements while nursing is also not recommended.

The effectiveness of melatonin in children and adolescents is still being investigated.

According to a 2026 research review, some studies have found benefits for older children (those ages 7 to 18 years), but evidence is lacking for younger children. The researchers also note that extended use and overdoses of melatonin have increased in younger children, and more studies are needed to evaluate melatonin’s long-term safety in these children.

Some research also suggests that long-term melatonin use may delay puberty — as a natural decline in evening melatonin levels is associated with the onset of puberty — but more research is needed.

Because researchers don’t yet understand the long-term effects of melatonin use in children, it may be best to help your kids implement proper sleep practices first before trying melatonin.

Always talk with your child’s pediatrician before starting them on melatonin. They will be able to take your child’s individual needs into account and inform you about safe dosages if melatonin is an appropriate option for your child.

Though melatonin is typically considered safe for short-term use in healthy and nonpregnant people, its long-term safety hasn’t been studied extensively.

If you find that you need melatonin every night to help you sleep, it’s time to talk with a healthcare professional. An underlying condition may be causing chronic sleep disruptions.

There may be a variety of reasons why a doctor may not recommend melatonin, including a lack of regulation for supplements, not enough research into long-term safety, or because melatonin can interact with a variety of medications.

If you want to try melatonin, it’s worth a conversation with your doctor. They may recommend it on an individual basis for short-term sleep issues.

If you’re considering melatonin, talk with a doctor, pharmacist, or sleep specialist first to find out whether it’s right for you and whether it might interact with any medications you’re taking.

Then, try to stick with the lowest dose that helps you fall asleep. Melatonin is generally well tolerated, although mild side effects are possible.

If you’re consistently taking melatonin because of sleep issues, talk with a healthcare professional to determine whether an underlying condition might be present.