Melatonin is a well-known sleep supplement, and since it is readily available online and in stores, it’s important to know how to safely use it. One of the questions that might come up is if it’s safe to take melatonin every night, especially over the long term.
In this article, we break down what the experts are saying on this topic. We’ll also cover the potential side effects of melatonin, how to properly use it, and more. Most importantly, though, if you’re interested in taking melatonin, you should consult your healthcare provider first, especially if you take other medications or have certain health conditions that could be impacted by melatonin use.
Should You Take Melatonin Every Night?
Experts have generally advised people to use melatonin short-term only. For example, the official recommendation from the National Health Service (NHS) of England is a maximum of 13 weeks for adults1 and two to three weeks2 for children, with the stipulation that it can be used longer-term if recommended by a specialist.
Experts give this advice with caution because there is not enough research looking at the effects of long-term melatonin use, especially in children.
However, in 2023 a review of studies3 was published. This review looked at 55 recent studies, mostly from the past five years, to learn more about the effects of taking melatonin long-term.
The researchers concluded that taking melatonin every night at low to moderate dosages (less than 6 milligrams per night) appears to be safe with no long-term negative effects.
They added that long-term melatonin use may even be beneficial for certain populations, like those with autism spectrum disorder (ASD) and Alzheimer’s, as well as older adults in general.3
According to the research, taking melatonin every night “may greatly benefit aging individuals given its relatively safe profile, potential anti-aging effects, mitigation of cognitive decline, and unequivocal improvement in sleep quality.”
The researchers do note that more studies are warranted – especially when it comes to children. Most of the information we have on nightly melatonin usage is for children with ASD, attention-deficit/hyperactivity disorder (ADD/ ADHD), or other neurodevelopmental disabilities. This research finds that using melatonin every night for these specific pediatric populations seems to be safe and beneficial overall.3
However, for neurotypical kids, we don’t have enough information about the effects of taking melatonin every night. With this lack of research, we’d recommend that your child only take melatonin short-term, unless expressly advised otherwise by their pediatrician.
Melatonin Side Effects
Some people may experience short-term side effects with melatonin. The most common side effects4 include:
- Headache
- Dizziness
- Drowsiness
- Nausea
Less commonly, some people may experience short-term feelings of depression, mild tremors, mild anxiety, abdominal cramps, irritability, reduced alertness, or confusion.4 If you experience any of these side effects, you can try lowering your dose or stop taking melatonin altogether.
You should always consult with a healthcare provider or sleep specialist before taking melatonin, changing your dose, or stopping your use altogether.
According to the NHS, the following medications can interact with melatonin5:
- Antidepressants like Luvox and Fevarin (fluvoxamine) or Elavil and Vanatrip (amitriptyline).
- Blood pressure medications, such as Vasooxyl (methoxamine) and Catopres (clonidine)6.
- Benzodiazepines such as Restoril (temazepam) or Valium (diazepam)
- Nonsteroidal anti-inflammatory drugs (NSAIDs) like Advil (ibuprofen), Aleve (naproxen), or (Cambia) diclofenac.
- Opiates such as Tuzistra XR® (codeine) or Morphabond® (morphine).
- Oestrogens/Estrogens (contained in hormonal birth control and hormone replacement therapy).
- Psoriasis and skin disorder medications such as Methoxsalen (psoralen)
- Epilepsy medications such as Carbatrol (carbamazepine) and Epitol (carbamazepine).
- Certain antibiotics like quinolones or rifampicin. A brand example of a drug in the quinolone group would be Cipro7 (ciprofloxacin), and a brand example of a rifampicin is Rifadin.
- Medications for stomach ulcers like Tagamet HB (cimetidine).
- Schizophrenia medication such as Mellaril (thioridazine).
- Insomnia medications such as Sonata (zaleplon), Ambien (zolpidem), or Imovane (zopiclone).
- Medicines for blood clots such as Coumadin (warfarin).
It is also advised that you use caution if you’re taking any herbs or supplements that reduce blood clotting or are taking any herbs that induce drowsiness8, like Valerian root or St. John’s wort.4
If you’re taking any of these prescription medications or supplements, ask your healthcare provider before starting melatonin.
Can You Become Addicted to Melatonin?
You cannot become physically or chemically addicted to melatonin, according to the Cleveland Clinic9. They add that while you may be psychologically dependent on melatonin, your body likely won’t become dependent on it.
This means that you won’t build up a tolerance to melatonin, which is when you must take more and more of something over time to get the same effects, and you won’t have withdrawal or detoxification symptoms if you decide to simply stop taking it. You will not need to wean yourself off of melatonin.9
The Cleveland Clinic goes on to say there’s no evidence to show that taking melatonin over an extended period will cause your body to stop producing as much of its own melatonin, but research is needed for long-term effects.9
What Is a Safe Melatonin Dosage?
A generally safe melatonin dosage is between 1 and 3 milligrams10 for most people.The maximum recommended dose of melatonin is 10 milligrams, but this is considered a very high dose.1 According to the Cleveland Clinic, doses this high have limited use and are usually only beneficial for people with issues like REM sleep behavior disorder.9
When Should You Take Melatonin?
If you’re looking to use melatonin for sleep, the American Academy of Sleep Medicine11 (AASM), says melatonin is the most effective for circadian rhythm sleep disorders like jet lag, shift work, and sleep-wake phase disorders.
Jet Lag
Research suggests that taking melatonin supplements can reduce the effects of jet lag by up to 50 percent12. To get the most of out your melatonin for jet lag, you should begin taking melatonin about two hours before your intended bedtime, starting a few days before you leave for your trip.10
Shift Work
According to the AASM, shift workers who must work through the night and sleep during the day, should take melatonin after the end of their shift, about one or two hours before their morning bedtime.11
You’ll also want to make sure your bedroom is as dark as possible if you must sleep during the day. Blackout curtains are a great way to achieve this, especially for daytime sleep.
Sleep-Wake Phase Disorders
Taking melatonin may help with the three types of sleep-wake phase disorders: delayed-, advanced-, and free-running sleep-wake-phase disorders.11
If you have delayed sleep-wake phase disorder, your circadian rhythm is about two hours later than most people’s, meaning, you go to bed very late and wake up very late. It seems effective to take melatonin two hours before your intended bedtime, to help reset your circadian rhythm.11
People with advanced sleep-wake phase disorder go to bed very early and wake up very early. In this case, it may help to prolong light exposure13 at night, and then take melatonin one to two hours before your desired bedtime.
Finally, free-running (or non-24-hour) sleep-wake rhythm disorder is a sleep disorder more common in the totally blind population14.
Research shows that taking melatonin one or two hours before the desired bedtime can support the circadian rhythms of people who cannot otherwise sense darkness.14
Insomnia
The AASM says that melatonin is a great tool for occasional insomnia, but recommends cognitive behavioral therapy for insomnia15 (CBT-I) for more chronic insomnia. It’s also a good idea to consult with your doctor if your insomnia persists as they may be able to provide you with additional treatment options.
Neurodevelopmental Disorders
As mentioned, research shows that long-term melatonin use can be beneficial for people with neurodevelopmental disorders like ASD, ADD, and ADHD.3 The research found that melatonin could not only improve sleep in these populations but can also improve behaviors and mood.
If you or somebody you know has a neurodevelopmental disorder, and you think melatonin may help, talk to your doctor.
Who Should Avoid Melatonin?
According to the NHS, the following groups of people should avoid melatonin use16:
- Those with an allergy – If you have ever had an allergic reaction to melatonin, you should not take these supplements.
- People with autoimmune conditions – If you have an autoimmune disorder like rheumatoid arthritis, lupus, or multiple sclerosis, the NHS recommends you avoid melatonin.
- People with liver or kidney issues – The NHS cautions against taking melatonin if you have liver or kidney problems. Likewise, there are some people who may be able to safely take melatonin, but should discuss it with their doctor first, as they may be at greater risk for negative side effects.
- Women who are pregnant, breastfeeding, or trying to conceive – There is limited research looking at the safety of taking melatonin while pregnant or breastfeeding, so it is unclear how safe it is.
- People with seizure disorders – Melatonin may help people with epilepsy reduce their number of seizures, while other research suggests it may increase them.6 Since there is conflicting information on the subject, do not take melatonin without your doctor’s guidance.
- Those with depression – Some studies show melatonin supplements may worsen depression symptoms in those diagnosed with depression.6
- People with diabetes – Again, there is currently a debate in the scientific world as to whether melatonin is beneficial or harmful17 for those with diabetes. If you have diabetes, talk to your doctor before starting melatonin.
- People with high blood pressure – Melatonin may help lower your blood pressure.6 However, this may be a problem if you’re already on blood pressure medication.
- People taking certain prescription medications or dietary supplements – As mentioned above, there are certain medications and supplements that melatonin could interact with. Some examples include antidepressants like Fevarin (fluvoxamine) or Vanatrip (amitriptyline) and medications for blood clots such as Coumadin (warfarin).5 These are just some examples, though, so be sure to consult your healthcare provider before taking melatonin.
Melatonin Alternatives
If you’re advised against using melatonin or it just doesn’t work well for you, you could try one of these other sleep aids. Even though these are supplements, you should discuss them with your healthcare provider before introducing them into your regimen.
Check out our guide: Natural Sleep Aids.
Chamomile Tea
This herbal tea is made up of dried chamomile flowers18.
Chamomile flowers are considered a mild sedative, acting on the benzodiazepine receptors in the brain. This should make you sleepy, but the effect shouldn’t be overwhelming.18
Valerian Root
Valerian root19 has been shown to reduce anxiety and induce sleepiness in people and is generally considered to be a safe sleep aid. However, you should be careful mixing it with any other sleep aids or prescription medications.
CBD
CBD, or cannabidiol, can come from the hemp plant20 and is a naturally occurring component in cannabis. However, on its own, CBD does not cause any sort of high as it is different from the tetrahydrocannabinol (THC) compound 21.
A 2023 study found that CBD use over eight weeks improved sleep quality22.
Magnesium
Magnesium is a mineral vital to many functions in our bodies23, including protein synthesis, muscle and nerve function, blood glucose control, and blood pressure regulation. Research shows that certain types of magnesium supplements can induce relaxation in the muscles and mind24, which could lead to better sleep.
Tryptophan
You might have heard of tryptophan as the component in turkey that makes you sleepy. Turkey is one food that contains this essential amino acid, and you can also buy it as a supplement. Tryptophan helps boost serotonin and melatonin25 levels, which can help promote sleepiness.
Tart Cherry Juice
If you want to avoid supplements entirely, try drinking some tart cherry juice about an hour before bedtime. Research shows that tart cherry juice26 can reduce inflammation and improve sleep quality.
Tips for Better Sleep Without Melatonin
Melatonin is not for everyone, and it doesn’t come without risks of side effects. In fact, before reaching for any supplements to help you sleep, you’ll want to ensure that your lifestyle and behaviors are setting you up for a good night’s rest.
- Stick to a consistent sleep schedule (even on weekends)
- Wind down with a relaxing bedtime ritual each night
- Put away your phone and other screen devices one to two hours before bedtime
- Get plenty of exercise during the day
- Make sure your bedroom is dark, quiet, and cool
- Invest in a comfortable bed, find our picks for the best mattresses here
- Get outside in the morning and dim the lights at night to help regulate your circadian rhythm.
Frequently Asked Questions
What happens if I take melatonin every night?
Recent research shows that taking melatonin every night doesn’t seem to have many negative effects for most people.3 That said, many experts still do not recommend taking melatonin every night at this time for an extended period of time.1
Can long-term use of melatonin be harmful?
At this time, it doesn’t look like long-term melatonin use is harmful, however, we are still learning more about melatonin, and studies are ongoing. Talk to your healthcare provider before deciding to take melatonin, especially if you’re interested in using it for longer than 13 weeks.1
What is the downside of taking melatonin every night?
At this time, studies show no negative effects from taking melatonin long-term for adults, and we still don’t have enough information about children taking melatonin long-term.3 Either way, it’s still good to get your healthcare provider’s opinion about melatonin as they know your health history and can provide more detailed guidance.
Natalie Grigson
Writer
About Author
Natalie is a content writer for Sleep Advisor with a deep passion for all things health and a fascination with the mysterious activity that is sleep. Outside of writing about sleep, she is a bestselling author, improviser, and creative writing teacher based out of Austin.
Side Sleeper
References:
- “How and when to take melatonin”. National Health Service. Last modified February 13, 2023.
- “Do’s and Don’ts of Giving Melatonin to Kids”. Children’s Healthcare of Atlanta. Last modified April 5, 2021.
- Givler, Donald., et al. “Chronic Administration of Melatonin: Physiological and Clinical Considerations”. Neurology International. 2023.
- “Melatonin”. Mayo Clinic. Last modified August 10, 2023.
- “Taking melatonin with other medicines and herbal supplements”. National Health Service. Last modified February 13, 2023.
- “Melatonin”. Mount Sinai. Webpage accessed July 23 2024.
- “Ciprofloxacin (Oral Route)”. Mayo Clinic. Last modified July 1, 2024.
- “Warning: Do Not Mix These Supplements”. Caregivers Nova Scotia. Webpage accessed January 18, 2024.
- “The Truth About Melatonin Addiction”. Cleveland Clinic. 2022.
- “Melatonin for Sleep: Does It Work?”. Johns Hopkins Medicine. Webpage accessed January 16, 2024.
- “Melatonin”. American Academy of Sleep Medicine. 2020.
- Arendt PhD, Josephine., Aunlinas MD PhD, Anna. “Physiology of the Pineal Gland and Melatonin”. Endotext. Last modified October 30, 2022.
- “Circadian Rhythm Sleep Disorders”. Cleveland Clinic. Last modified April 1, 2020.
- Quera Salva, Maria Antonia., et. al. “Non-24-Hour Sleep–Wake Rhythm Disorder in the Totally Blind: Diagnosis and Management”. Frontiers in Neurology. 2017.
- “Missing the mark with melatonin: Finding the best treatment for insomnia”. American Academy of Sleep Medicine. 2021.
- “Who can and cannot take melatonin”. National Health Service. Last modified February 13, 2023.
- Garaulet, Marta., et al. “MELATONIN EFFECTS ON GLUCOSE METABOLISM: TIME TO UNLOCK THE CONTROVERSY”. National Library of Medicine. 2020.
- Srivastava, Janmejai K., Shankar, Eswar., Gupta, Sanjay. “Chamomile: A herbal medicine of the past with bright future”. National Library of Medicine. 2010.
- Shinjyo, Noriko., Waddell, Guy., Green, Julia. “Valerian Root in Treating Sleep Problems and Associated Disorders-A Systematic Review and Meta-Analysis”. National Library of Medicine. 2020.
- Grinspoon MD, Peter. “Cannabidiol (CBD): What we know and what we don’t”. Harvard Health Publishing. 2021.
- Bauer MD, Brent A. “What are the benefits of CBD — and is it safe to use?”. Mayo Clinic. 2022.
- Kisiolek, Jacob N., et al. “Eight Weeks of Daily Cannabidiol Supplementation Improves Sleep Quality and Immune Cell Cytotoxicity”. Nutrients. 2023.
- “Magnesium”. National Institutes of Health. Last modified June 2, 2022.
- “Magnesium for Anxiety: Does It Help?. Cleveland Clinic. 2023.
- Nagashima, Shunsuke., et al. “Can tryptophan supplement intake at breakfast enhance melatonin secretion at night?”. Journal of Physiological Anthropology. 2017.
- Losso PhD, Jack N. “Pilot Study of Tart Cherry Juice for the Treatment of Insomnia and Investigation of Mechanisms”. National Library of Medicine. 2018.