What Is Melatonin? Dosage, Side Effects, Sleep Usage, and Overdose Risk

As per some experts, taking melatonin supplements in high amounts can disrupt circadian rhythms and, consequently, regular sleep patterns. Their interactions with the body's natural substances may also contribute to developing specific symptoms.

There is no such thing as a "normal" dose because everyone reacts differently to medication. Because of this, efforts to determine the threshold at which an overdose occurs are made more difficult.

When taken at low doses, melatonin is not only practical but also wholly risk-free. There is a possibility that adverse symptoms, which include headaches, dizziness, and nausea, will occur. When taken excessively, melatonin levels in the body can increase significantly. The symptoms of an overdose might vary from person to person, but the most common ones are feeling sleepy during the day, experiencing nausea, and having elevated blood pressure.

What Is Melatonin?

The hormone melatonin is crucial in maintaining a regular wake-sleep cycle, sometimes known as the body's "biological clock." There is no need for a prescription to get melatonin in the United States; it is widely available without a doctor's visit at stores that carry OTC vitamins and supplements.

The addition of melatonin has been advocated for various illnesses, ranging from sleep disorders to cancer treatment; however, solid evidence for many of these uses is lacking. Extensive study has been done on the effects of this on jet lag and other sleep disorders.

The highest levels of endogenous (self-produced) melatonin in the body occur between 11 p.m. and 3 a.m. Noise levels at night are roughly ten times lower than during the day. The predawn readings are far lower than the daytime averages. The circadian cycle begins and ends with a rise and fall in endogenous levels, respectively, during the day and night.

The amino acid tryptophan is converted into the hormone melatonin with the help of serotonin, which is then produced and binds to receptors in the brain, eyes, and elsewhere to control sleep and alertness. The interval between the onset of the first and second half-life effects is relatively short (20-50 minutes). The CYP450 enzyme system in the liver metabolizes it, and the resulting byproducts are excreted in the urine and feces.

Productivity decreases in the summer when the days are longer and increases in the winter when the days are shorter. At night, artificial light (from sources such as cell phones and televisions) suppresses creativity and can interfere with sleep. Reduced nocturnal melatonin release is a potential factor in the aging-related sleep disturbances and early morning waking prevalent among the population of the over-60 set.

Melatonin Dosage

Melatonin can help overcome jet lag as a sleep aid because it induces sleep at unnatural hours.

It has been found that initial dosages of melatonin between 0.3 and 0.5 mg are effective for treating jet lag. If you need to take 0.5 mg of melatonin and can only find 1 mg tablet, you can cut the tablet in half. The United States typically markets higher doses (up to 10 mg), even though they may be associated with more adverse effects, such as Headache, grogginess the next day, or vivid dreams. Melatonin's adverse effects may be magnified in the elderly.

It's best to begin treatment with the smallest possible dose. A Cochrane analysis found that doses more than 5 mg did not significantly outperform lesser levels. There is some evidence that higher dosages of melatonin can cause an increase in melatonin levels above and above what is considered healthy.

Risks and Side Effects of Melatonin

There aren't many harmful effects or hazards associated with taking melatonin pills. Most of the time, melatonin won't affect your body or sleep cycle if you take it at a safe, controlled dose. Melatonin supplements are not standardized in manufacturing or packaging; therefore, buying from a reliable source is essential. The FDA does not test or regulate melatonin for purity, safety, or efficacy.

Interactions between melatonin and some pharmaceuticals can be dangerous. Especially in the below cases −

  • Medication for preventing pregnancy related to high blood pressure

  • Treatments for diabetes and the immune system (immunosuppressants)

Melatonin pills may cause the following adverse effects in some people −

Feelings of sleepiness or grogginess during the day, even after waking up, which can be exceptionally bothersome if you work night shifts or have maintained consistent sleep patterns for a long time − dizziness − disorientation − occasional headaches or migraines; and brief, unexplained bouts of depression.

What Happens When You Overdose on Melatonin?

One can take melatonin in excess, but doing so can lead to severe repercussions for one's health, and there have been very few clinical studies conducted on this subject. The intensity of the symptoms varies depending on the amount that was consumed as well as the physiology of the individual.

When taken in excess, melatonin might have the reverse of its intended effect. It suggests that having an excess amount of sleep hormone in your system can make it more difficult to nod off.

Extreme Melatonin Withdrawal Symptoms −

It is possible to experience the following side effects from taking too much melatonin −

  • Variations in blood pressure Headache

  • Drowsiness

  • Vomiting

Those with low baseline melatonin levels, such as the elderly, may be more susceptible to the unwanted effects of this treatment

Melatonin Sleep Usage

Melatonin is a hormone that plays a role in controlling sleep patterns and wakefulness. Even in their natural environments, the highest melatonin levels in the blood are found at night. Some evidence suggests that taking melatonin supplements can assist with sleep issues such as delayed sleep.


The natural melatonin in your body controls your sleep-wake cycle. In addition to having antioxidant properties, it helps the body's immunological system.

Melatonin is a supplement frequently used to treat insomnia and other sleep disorders and to normalize sleep patterns that have been disrupted due to jet lag or shift work. 

Melatonin overdose cases are low, but it can potentially cause serious health problems; nevertheless, there is a lack of clinical data. When treating an overdose with melatonin, the first thing to be done is to cease taking the drugs.

Updated on: 03-Feb-2023


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