Can You Overdose On Melatonin? How much Melatonin is too much?

by sleep supplements, sleep wellness

Why we sleep at night…

An odd question, right? Not for us and it shouldn’t be for you if you really want to understand your body.

We don’t stay awake and active at daytime and sleep at night by chance or on a whim. Our brain controls hormones, body temperature and other factors, which make our Circadian Rhythm (sleep and wake cycle) work.

One of the hormones that plays a big part in the process is Melatonin. Today, we’ll be talking about the DOs and the DONT’s of using it safely and most importantly, avoiding a Melatonin overdose.

woman in bed watching melatonin pills side table

What doctors recommend

Smart choice with sleeping aids

Melatonin works best in synergy because it’s plasma half-life is short – 20 to 50 minutes.

In other words, to get most out of it, the best sleep aids combine it with L-theanine, Valerian root & Chamomile.

Currently rated as safest and non-habbit-forming sleep aid is Luna with a user satisfaction rate of 92%. You can see what people are sharing about Luna in the link below.

Luna sleep aid

luna button

Skip to the part of this guide you’re interested in

Basic facts about Melatonin

What is Melatonin?

It’s a hormone made by the pineal gland which is located in the central part of the brain. Along with other hormones, it regulates our sleep-wake cycle. It can also be found in meats, grains, vegetables and fruits, but in small amounts.

There’s also a “synthetic” melatonin in a form of a supplement – which is what we’ll be talking about today.

How it’s regulated

The amount of melatonin in the body is related to light, during the day the gland is inactive.

When the sun goes down it the production of Melatonin kicks in and as it gets darker the level of rises and stays high all through the night. It drops with the first rays of morning sun.

young girl depressed winter

What’s “Melatonin depression”?

In the short winter days our bodies adapt to by changing our internal clock and producing melatonin a bit earlier or later than usual.

The condition is known as “Melatonin depression”.

It mimics all the effects of being depressed but is not diagnosed or treated as clinical depression. Knowing what it is often enough to make the effects milder.

When to supplement

Lack of natural melatonin might call for supplementation. It can help treat jet lag, insomnia and seasonal affective disorder.

For people who work night shifts or had a sudden change of their sleep schedule it helps control sleep patterns and get them back into their routine.

Melatonin supplements are also used with patients who have trouble sleeping after surgery.

So, in general, we need it so we can have a healthy sleep and rest. If you have sleep problems, before trying heavy medications you should start with something your body is familiar with, and the supplements can help you with that.

It is not, however, a long-term solution for sleep problems.

melatonin pills concept illustration

Can you overdose on Melatonin?

How much Melatonin is too much?

Generally, doses up to 5mg are considered to be safe, but a precise answer to the question “how much is too much melatonin?” will depend on a range of factors, from your weight and gender to your age and sensitivity to the substance.


The Mayo Clinic recommends the following doses:

  • Doses in the range between 0.3 and 10 mg of Melatonin, depending on the person – for most sleep problems, unrelated to specific medical conditions
  • Doses in the range of  0.1 to 5 mg for insomnia problems in the elderly
  • For jet lag – doses in the range from 0.1 to 8 mg
  • To help with restless legs – 3 mg

Why you need to be cautious

Synthetic melatonin is very similar to the one that our bodies produce, but like with any other medication, you have to be careful.

Since it’s not marketed as a medicine but as a supplement, there were no rigorous testing and no official recommendation of a dosage you should take and no official numbers of what constitutes a melatonin overdose.

One thing is for sure – taking extremely high doses of melatonin will not help you sleep better. The safe dose is the one that is strong enough to get you to sleep but low enough not to give you any troubles. It also depends on your body weight, age and sensitivity.

young girl deep asleep melatonin pills spilled on table
young man taking pill before bed

One common cause of melatonin overdose

Body usually produces about 0.3mg per day, so anything between 0.2 to 1mg an hour before you go to bed, should work and it’s a good starting dose.

People often take pills just before they go to bed, so there is not enough time for them to take effect, so they take another one – a common way one might get into the “red zone”.

Also, it’s better to start with small dosages and work up from there. The 5 or 6mg and up to 8 are the highest doses that are considered to help you without overdosing.

Melatonin overdose symptoms

There are documented cases of effects that patients experienced when taking large doses of melatonin or taking it for a long period of time (usually more than 3 months).

What happens when you take too much Melatonin?

Some potential signs of an overdose:

  • Hypothermia
  • Hormonal changes (it can reduce the libido of both men and women, it’s also not to be used by pregnant women)
  • Drowsiness and confusion (day after the medication was taken)
  • Reduced blood flow and joint pain
  • Irritability
  • Mood changes (sadness, worsening depression, anxiety)
  • Hallucinations, paranoia, nightmares and disorientation
  • Decrease in blood pressure and decreased flow of blood to the brain
  • Risk of seizures (especially if you have any type of seizure disorder)
  • Allergic reaction (in some rare cases)
  • Risk of liver damage (increased risk, especially with people who have problems with alcohol)
  • Stomach problems (nausea, pain, vomiting, diarrhea- even at small doses)
  • Increased risk of contracting immune system disorders (Hepatitis or Crohn’s disease)
  • Risks to infants through breast feeding (there are still not enough information about melatonin and its effects on children, so breast-feeding mothers are advised to avoid taking it)
  • Unknown effects to people with auto-immune disorders

Can you die from a melatonin overdose?

Case studies reveal only one overdose victim of melatonin so, in general, there’s no official info on a lethal dose of Melatonin.

In other words, the answer to the question “Can you take too much Melatonin?” is YES but the likelihood of it being life-threathening is, according to existing evidence, small.

Why do people overdose on Melatonin?

Psychological reasons and addictive behavior are the primary reasons behind taking too much melatonin.

Overdose itself is considered non-life threatening and its primary symptom is confusion. Although it can be quite unpleasant it’s unlikely to trigger any serious health problems.

People react differently to it, depending on their sensitivity, and whether you can OD on Melatonin will be different for each one of us.

If your health is good and you take reasonable doses and not for a long period of time, you shouldn’t see any serious problems.

Nevertheless, we must say, whatever dose you take, there is a chance that you will experience some side effects and if you think overdosed seek medical help.

Potential side effects of Melatonin

In any dosage level you may experience some side effects, for example:

  • Daytime sleepiness
  • Headaches, irritability, dizziness, confusion
  • Abdominal discomfort
  • Mild anxiety and short-lasting feeling of depression

Interactions with other substances

Melatonin supplements can interact with caffeine, alcohol, narcotics and various medications, including:

  • Diabetes medications
  • Blood-thinning medications (anticoagulants)
  • Blood pressure medicine
    Anti-psychotics, anti-anxiety drugs and some sedatives
  • Some muscle relaxants, other sleeping pills and pain killers
  • Meds that prevent seizures
  • Medications that suppress the immune system
    Birth control pills

With that in mind, if you are considering taking melatonin supplements and have some health conditions, you should consult your doctor first.

When buying melatonin supplements choose the synthetic ones, made in a lab, you should avoid “all natural” melatonin which comes from cow or pig brains.

Melatonin doses for children

Melatonin overdose in children – what doses are safe for your toddler?

Not regulated by the FDA

Melatonin is regulated as a food supplement by the FDA. Therefore there are no many studies about its effect. But there are a lot of people who have used it and gave their feedback.

Can they overdose on Melatonin?

Using melatonin has proven to help toddlers with sleep problems(you can see an interesting study on that here) both with falling asleep faster and sleeping calmly through the night. Since they usually go to bed earlier than adults, it is recommended to give them their doses in the afternoon.

The doses that are recommended for the children are low (0.5–1 mg) you can start with that and slowly increase them. Remember, this is a hormone, not a medication, and often the small doses are just enough.

Besides that, you should make sure that your children have good sleeping hygiene (with or without melatonin supplements) and that means appropriate sleeping schedule, limitation on light exposure etc.

Click here to read more about Melatonin for kids here

Melatonin doses for dogs

When to use it

Melatonin is widely used in treating health problems of dogs…ranging from alopecia, insomnia to separation anxiety. It has even shown great effects when it comes to training them.

If your dog is having problems the mart thing to do is visiting a vet so he can establish a diagnosis and the right dosage depending on your dog’s size and the condition they suffers from.

Basic dosages are:
  • 3 mg per dose for dogs weighing less than 25 lbs
  • 6 mg per dose for dogs weighing more than 25 lbs
5 forms used

Melatonin for dogs comes in the form of tablets, capsules, liquid, implant injections and powder. The best option are tablets and you can include them in your dog’s food if he refuses to take them.

Like with humans, using melatonin can have some side effects, such as sleepiness, nervousness, stomach pain and digestive disorders, itching etc.

Very young (age less than 12 weeks) or pregnant dogs should not be given melatonin. If your dog has allergies, seizures, kidney or brain problems or some bleeding disorders, you should avoid giving him melatonin.

Treatment for Melatonin Overdose

If you experience any strong side effects or think you overdosed on melatonin, you should ask for medical help.

The first step is stopping the intake of supplement altogether, rest and not engaging in any physical activity.

The rest of the treatment depends on the case and doctors opinion.


None of the information provided on this page is to be construed as medical advice. All the content presented is for informational and educational purposes only.


  • Bob Ozment

    Bob has been testing and writing about all things sleep (and especially blankets, air mattresses and folding beds), for 8+ years now. before that, he worked as a Quality Assurance Manager with one of the bigger names in the sleep industry. He holds a masters degree Statistics, Actuarial & Data Sciences from the central Michigan University at Mount Pleasant. He's one of the people who designs our producing testing and statistical models. He’s a stomach sleeper, but nobody’s perfect.