Is Melatonin Addictive?


Most people are familiar with melatonin supplements. In fact, you might have a spare bottle of pills rattling around in their nightstands in case of insomnia emergencies. But is it safe to take melatonin every night, or can it cause dependency?

Although some health experts don’t see eye to eye about whether or not the general population should be taking melatonin, one thing appears to be agreed upon across the board: melatonin is not an addictive substance.

Let’s take a closer look at the details about melatonin dependency, how to take melatonin supplements safely, and a bit of sleep science about how it actually works.

Is Melatonin Addictive?

Melatonin is a naturally occurring hormone that our bodies produce each night. This is a good sign that we won’t become chemically dependent or physically addicted to its supplemental form. 

If you currently take melatonin every night for insomnia or poor sleep, it’s possible that your sleep may suffer again once you stop taking it. However, that doesn’t mean it’s addictive.

One hallmark characteristic of addiction is needing more of a substance to feel the same effects (also known as increased tolerance). Melatonin does not have this effect—you won’t need to constantly up your dose to get the same sleep-inducing effects.

It also does not cause withdrawal symptoms or feelings of  “sleep hangover,” as you may see with many sleep medications.

Although our bodies don’t chemically rely on melatonin supplements to fall asleep,we are naturally dependent on our own melatonin.

Evidence also does not suggest that taking melatonin supplements will suppress our natural ability to produce melatonin.

That said, melatonin can be habit-forming. Just as brushing your teeth before bed is a habit, taking a melatonin pill might be one of yours, too. If you solely take melatonin out of habit, it’s probably time to take a break from it and see if it truly benefits your sleep. 

Overall, you don’t want to take too much melatonin or continue taking it forever, as there is not much long-term safety data on the supplement.

List of melatonin benefits and features

Melatonin Supplements: Side Effects and Dosage

The most frequent side effects of melatonin are headache and fatigue (which is usually the desired effect). Don’t take it within five hours of needing to drive. 

Other less common but still reported side effects include low blood pressure, high blood pressure, dizziness, digestive upset, vivid dreams, confusion, mild anxiety, cramps, irritability, and depression. 

Studies have found no significant differences in side effects between people taking melatonin versus placebo.3

Melatonin can also increase the risk of bleeding in those taking it, so people on blood thinners should avoid it or ask their doctor or healthcare provider.

Melatonin Supplements Dosage

Melatonin supplements vary widely in dosages, ranging from 0.1mg to 20mg. 

According to a review paper published in Neurology International, less than 5mg per day of melatonin appears to be safe. However, the authors state that the optimal dosage has yet to be established and that doses of 1mg or lower may be as effective as higher amounts.4 

For those new to taking melatonin, starting at the lowest dose (like 0.5 to 1mg) could be beneficial. The amount of melatonin you take may depend on what you’re using it for (i.e., to treat insomnia or another sleep disorder versus simply as a sleep aid).

Melatonin is sold as a dietary supplement in the United States (in contrast to Japan, Australia, the EU, and the UK, which require a prescription). It’s essential to ensure your melatonin supplement is third-party tested for potency, purity, and quality.

Who Should Not Take Melatonin?

Pregnant and breastfeeding women are not advised to take melatonin, as there is not enough long-term safety data.

People on blood thinning medications or those with autoimmune or seizure disorders should also avoid it. 

Melatonin interacts with several prescription medications, including diabetes medications, anticonvulsants, antiplatelet drugs, oral contraceptives, blood pressure drugs, anti-anxiety medications, and immunosuppressants.

As always, ask your doctor if you’re unsure. 

How Does Melatonin Work?

Melatonin is a naturally occurring hormone produced by the pineal gland, a tiny organ shaped like a miniature pinecone (that’s where its name comes from!) located in the deep center of your brain. 

The pineal gland doesn’t get much action during the daylight hours, but when night time comes around, it gets to work. 

We need the amino acid tryptophan to create melatonin in the body. This is why people (somewhat erroneously) claim that Thanksgiving turkey puts them to sleep.5

Tryptophan gets converted into a compound called 5-HTP (5-hydroxytryptophan), followed by a transformation into serotonin, our “feel-good neurotransmitter,” a direct precursor to melatonin.

However, these conversions don’t happen all day long. Darkness is needed to stimulate the pineal gland to produce melatonin.

For people on a conventional sleeping schedule, melatonin is produced in the late evening (maybe around 8-10 pm, depending on the person). Nighttime melatonin levels are about ten times greater than in the morning, preparing your body for sleep by lowering blood pressure, body temperature, and the stress hormone cortisol.6 

Conversely, when light first hits your eyes in the morning, your retina sends a signal to a center in the brain’s hypothalamus called the suprachiasmatic nuclei (SCN). This tells the pineal gland to shut down melatonin production and perform some wake-up duties instead, like raising body temperature and releasing some cortisol to get you going on your day.5 

Both the timing of our sleep-wake cycle and melatonin synthesis are governed by the circadian rhythm, our body’s 24-hour internal clock.

Our circadian rhythms are controlled by light exposure.The SCN in the hypothalamus is responsible for keeping the circadian rhythm’s pace.5 

Ideally, melatonin is only produced after sundown and is halted during the day. However, many things can disrupt this ancient biology, especially artificial light and electronic usage at night. Bright, unnatural lights can significantly delay melatonin production and worsen sleep (yet another reason to stop scrolling social media before bed!).

Melatonin supplements are thought to work best to treat insomnia and for people with sleep disorders or disrupted circadian rhythms, including those working night shifts or traveling across multiple time zones (aka jet lag).7,8 

Taking melatonin also helps regulate the circadian rhythms of people with insomnia and night owls, especially for reducing sleep onset latency, or how long it takes to fall asleep.9 

Research also suggests that people with autistic spectrum disorder (ASD) may benefit from supplemental melatonin. A meta-analysis of 15 studies found that melatonin use significantly improved total sleep time, sleep latency, and sleep efficiency in people with ASD.10

Lastly, it’s worth mentioning that melatonin is not just beneficial for sleep—it also exhibits anti-inflammatory and antioxidant properties. For this reason, it’s been studied for its role in improving cardiovascular, cognitive, bone, kidney, and metabolic health.11 

Is Melatonin Addictive? FAQs

Is it OK to take melatonin every night?

It’s generally considered okay for adults to take melatonin every night, but you’ll probably want to take some time off them every once in a while to see how you do without them. While they aren’t considered unsafe to take every night, we don’t have enough long-term safety data to say that for sure. Sleep experts at Johns Hopkins Medicine state that “it’s safe for most people to take nightly for one to two months.”12 The lowest dose you can use while still benefiting your sleep is ideal.

Is it OK to take melatonin long-term?

Long-term safety data on melatonin has yet to be established. It’s probably best to cycle your melatonin use and not take it for longer than one to two months at a time. People with sleep disorders may see the most benefit from taking melatonin for longer periods of time.

Can you build up a tolerance to melatonin?

No, it’s not thought that you build up a tolerance to melatonin. It’s also not thought that you can be addicted to melatonin. This means you should not need more of it if you take it for longer periods of time. That said, you can take too much melatonin, as high doses are more likely to cause adverse effects. 

Can you stop melatonin cold turkey?

Yes, you can stop melatonin cold turkey, as it is not a supplement that will cause withdrawal symptoms or melatonin addiction.

  1. Cardinali, D. P., Srinivasan, V., Brzezinski, A., & Brown, G. M. (2012). Melatonin and its analogs in insomnia and depression. Journal of pineal research, 52(4), 365–375.
  2. Matsumoto, M., Sack, R. L., Blood, M. L., & Lewy, A. J. (1997). The amplitude of endogenous melatonin production is not affected by melatonin treatment in humans. Journal of pineal research, 22(1), 42–44.
  3. Buscemi, N., Vandermeer, B., Hooton, N., Pandya, R., Tjosvold, L., Hartling, L., Baker, G., Klassen, T. P., & Vohra, S. (2005). The efficacy and safety of exogenous melatonin for primary sleep disorders. A meta-analysis. Journal of general internal medicine, 20(12), 1151–1158.
  4. Givler, D., Givler, A., Luther, P. M., Wenger, D. M., Ahmadzadeh, S., Shekoohi, S., Edinoff, A. N., Dorius, B. K., Jean Baptiste, C., Cornett, E. M., Kaye, A. M., & Kaye, A. D. (2023). Chronic Administration of Melatonin: Physiological and Clinical Considerations. Neurology international, 15(1), 518–533.
  5. Tordjman, S., Chokron, S., Delorme, R., Charrier, A., Bellissant, E., Jaafari, N., & Fougerou, C. (2017). Melatonin: Pharmacology, Functions and Therapeutic Benefits. Current neuropharmacology, 15(3), 434–443.
  6. Touitou Y. (2001). Human aging and melatonin. Clinical relevance. Experimental gerontology, 36(7), 1083–1100.
  7. Liira, J., Verbeek, J. H., Costa, G., Driscoll, T. R., Sallinen, M., Isotalo, L. K., & Ruotsalainen, J. H. (2014). Pharmacological interventions for sleepiness and sleep disturbances caused by shift work. The Cochrane database of systematic reviews, 2014(8), CD009776.
  8. Cingi, C., Emre, I. E., & Muluk, N. B. (2018). Jetlag related sleep problems and their management: A review. Travel medicine and infectious disease, 24, 59–64.
  9. Auld, F., Maschauer, E. L., Morrison, I., Skene, D. J., & Riha, R. L. (2017). Evidence for the efficacy of melatonin in the treatment of primary adult sleep disorders. Sleep medicine reviews, 34, 10–22.
  10. Nogueira, H. A., de Castro, C. T., da Silva, D. C. G., & Pereira, M. (2023). Melatonin for sleep disorders in people with autism: Systematic review and meta-analysis. Progress in neuro-psychopharmacology & biological psychiatry, 123, 110695.
  11. Savage RA, Zafar N, Yohannan S, et al. Melatonin. [Updated 2024 Feb 9]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: 
  12. Johns Hopkins Medicine. Melatonin for sleep: Does It Work? 2024. Accessed at 

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