When to take it

When should I take melatonin?

By GyroscopeUpdated November 14, 20266 sources

It depends on what you want it to do. To fall asleep faster, take it 1 to 3 hours before bed, so between 8 and 10pm for an 11pm bedtime. To move your bedtime earlier for good, take 0.5 mg about 5 hours before your usual bedtime, which lands in the late afternoon or early evening.

The bottle says to take it before bed, so most people swallow it as they turn off the light. That’s how you’d time a sleeping pill. Your brain starts releasing its own melatonin in the evening, about 2 to 2.5 hours before you usually go to sleep, and a tablet tells your body clock the same thing at whatever hour you swallow it.

We’d pick the job first and the hour second. For most people that means 0.5 to 1 mg one to three hours before bed, lamps instead of overhead lights once it’s in, and two weeks of your own nights before you decide it works.

It’s like a reminder to start getting ready for bed. Set it to go off at bedtime and it’s too late to help.

Why does the hour change what it does?

Taken in the hours before your own melatonin starts, a tablet pulls your body clock earlier. Taken just after you wake up, it pushes it later. While you’re asleep it barely moves the clock at all. A team in Chicago mapped this in 2010. 34 adults took one pill a day for 3 days in a dim lab, each at a different hour, and the biggest moves earlier came when 0.5 mg was taken in the afternoon, 2 to 4 hours before their own melatonin started.

For falling asleep, earlier did better too. A 2024 analysis of 26 trials found that the longer the gap between the dose and sleep, the more it cut the time it took to fall asleep. The authors suggested about 3 hours before the bedtime you want, against the schedule most clinics used, 2 mg half an hour before bed. Small doses worked early as well. In a 1995 sleep lab test, 0.3 or 1 mg at 6, 8 or 9pm all shortened the time to fall asleep, with no hangover on the morning tests.

When to take it to fall asleep faster

Start with 0.5 to 1 mg.

When to take it to move your bedtime earlier

The time you wake up on a day with no alarm predicts when your own melatonin starts, within about an hour for most people in the original study. Take 0.5 mg 2 to 4 hours before that.

The surprise for most people is the afternoon. If you sleep until 8am on weekends, the best hour to move your clock earlier is around 6:35pm, long before you’d think about bed. Then keep the room dim. Ordinary room light in the hours before bed made melatonin start later in 99 percent of 116 young adults in a 2011 study, which is why light does the same job, harder.

The equation behind that table came from young people sleeping on their own schedule in summer. It can be further off for older adults, shift workers and anyone whose alarm runs their life, so treat the times as a starting point and watch your own nights.

When the tables don’t apply

If you’re under 18, pregnant or breastfeeding, or take a prescription medicine every day, these windows aren’t for you. Start with the children’s answer, the pregnancy answer or the medicines answer. For a trip there’s the jet lag planner, and for nights at work the night shift planner. To move your bedtime later there’s no pill window at all, since the hour that does it is just after waking, when a tablet makes you drowsy. Evening light and a later wake time do that job.

Put your own wake time into the calculator below, or take the quiz for your window, your dose and a two-week test. Don’t drive after a dose.