Melatonin Hangover: Why You're Groggy & How to Fix It

Melatonin—also called the sleep hormone—is the main hormone secreted by the brain’s pineal gland (1). Derived from tryptophan, melatonin runs the show when it comes to sleep and the upkeep of your circadian rhythm (your brain’s 24-hour internal clock) (2, 3).

By controlling your sleep-wake cycle, melatonin helps to promote sleep while inhibiting wake-promoting signals through interactions with its MT1 and MT2 receptors (two types of melatonin receptors).

Despite not being approved by the FDA (Food and Drug Administration), synthetic melatonin is the first-line sleep aid for those suffering from insomnia. It’s relatively safe, has a very low risk of side effects, and helps you fall asleep faster, stay asleep longer, and get deeper, higher-quality sleep (4, 5).

A melatonin hangover is one of the most common side effects of melatonin. It results in drowsiness, daytime sleepiness, headaches, and in some cases, nausea (4).

It typically arises from either taking too much melatonin or taking it too late into the night. It can also be caused by continuous-release melatonin tablets, meaning that the tablet is released into the bloodstream over the course of several hours rather than just one to two hours. And of course, things like metabolism, genetics, and one’s overall energy level also contribute to a melatonin hangover.

Luckily, it’s possible to combat this zombie-like hangover…

Enter: A magnesium supplement.

Melatonin, when combined with magnesium, significantly increases the body’s melatonin levels, while significantly decreasing cortisol (the body’s stress hormone). Although magnesium deficiency is quite rare, 50% of Americans don’t get enough of it (6). This, in turn, can lead to a disrupted circadian cycle, a reduction in melatonin production, and the onset of sleep disorders (7).

Thus, with a high-quality sleep aid supplement that contains both melatonin and magnesium, you’ll be able to experience more sleep (and better sleep), while having the luxury of falling asleep faster (7).

Did you know that your body’s melatonin levels decline as you age (8)?

No wonder deep sleep becomes more and more difficult with each passing year.

But don’t worry, you don’t need to load up on melatonin every evening just to get a good night’s sleep. Instead, you can simply take between 0.5 and 5 milligrams of melatonin one hour before bedtime (9).

Why an hour before bedtime?

Because your brain naturally begins to produce melatonin about one to two hours before you go to sleep. So, taking a melatonin supplement during that time period will further enhance its production (9).

To date, there isn’t any evidence suggesting that people develop a tolerance to melatonin. However, refrain from taking it with benzodiazepines, zolpidem, and alcohol, as it can lead to excess sedation (4).

Melatonin kicks in within 20 minutes to two hours of taking it (10).

Wondering if melatonin will make you oversleep?

Well, melatonin’s half-life—the time it takes a substance to decrease to half of its starting dose in the body—isn’t very long. Depending on the formulation (whether it’s an immediate-release, extended-release, or a combination of the two), it takes about one to two hours at most (11, 4).

Thus, for it to be completely out of your system, it will take approximately four to five half-lives. So, for melatonin, it will take anywhere from 4 to 8 hours (11).