BRAND NAME: Pineal hormone, N-acetyl-5–methoxytryptamine

Melatonin supplement is an oral prescription and over-the-counter drug. It belongs to a class known as sedative/hypnotics, used to treat sleep disorders and other problems. Unlike with other sleep medications, you are unlikely to become dependent on melatonin, have a diminished response after repeated use (habituation) or experience day drowsiness.

What is Melatonin?

It is a natural hormone secreted by the pineal gland in the brain. Melatonin levels vary in 24-hour cycles and are controlled by a biological clock (our body clock). Melatonin secretion and release in the brain are connected to the time of the day, increasing when it’s dark and decreasing when there is a bright light. That is why it is often called ‘the hormone of darkness’ and its production declines with age.

What does Melatonin do?

Melatonin plays a vital role in helping to regulate the internal biological clock cycle of sleep and wakefulness. In regards to sleep, your body releases melatonin 2 hours before you go to sleep thereby preparing your body for sleep and during the early hours of the morning, the level of melatonin decrease thereby preparing your body for waking up. Some people who have insomnia (trouble sleeping) have low levels of melatonin. Adding melatonin supplements might help them sleep.

What is Melatonin used for?

Melatonin is commonly used to treat various conditions such as:

Insomnia: Melatonin helps to relief insomnia (the inability to fall asleep) by improving your total sleep time, sleep quality, and time required to fall asleep.

Jet lag: Some research shows that melatonin can improve jet lag symptoms, such as alertness and movement coordination. It also improves other jet lag symptoms like day drowsiness and tiredness.

Circadian rhythm sleep disorders in the blind: Melatonin helps to improve these disorders in adults and children.

Shift work disorder: melatonin may help to improve daytime sleep, quality and duration in people whose jobs requirement are to work outside the traditional morning to the evening schedule.

Delayed sleep-wake phase sleep disorder (trouble falling asleep): In this disorder your regular sleep pattern is delayed by two hours or more, causing you to go to sleep later and wake up later. Melatonin helps to decrease the length of time needed to fall asleep in young adults and children who have trouble falling asleep.

Sleep-wake cycle disturbances: Melatonin may help treat these disturbances in children and adolescents with intellectual disabilities, autism, and other central nervous system disorders.

Melatonin possibly useful for ringing in the ears, chronic fatigue syndrome, Alzheimer’s disease, depression, fibromyalgia, headaches, irritable bowel syndrome (IBS), osteoporosis, tardive dyskinesia (a movement disorder), cancer, menopause, epilepsy, sunburn protection, infertility, and birth control.

How to use Melatonin?

Melatonin is relatively safe, and it is therefore available over-the-counter at pharmacies and health stores. It is available in different dosage forms like tablets, capsules, liquids and sprays.

The strength of the melatonin dose may vary from 1mg up to 10mg or more. Remember that the FDA (Food and Drug Administration) does not regulate melatonin, and the production standards are not strictly implemented. Therefore, it is recommended to purchase from a reputable source.

The prefered time to take an oral melatonin supplement is at bedtime, 30 minutes before going to bed, as it reaches maximum concentration in your blood after 30 minutes. Take this supplement with or without food.

It is not habit-forming supplement, and you will not become addicted to it. Therefore, if you find it helpful in improving your sleep pattern, you may use it on a regular basis. There is some caution advised in children and pregnant women due to its potential effects on other hormones.

What are the side effects of Melatonin?

Melatonin is relatively safe when taken by mouth or injected into the body for a short period (up to 2 years in some people).

Some of the common side effects of melatonin are daytime drowsiness, depressed mood, feeling irritable, stomach pain, headache, or dizziness.

Seek emergency medical assistance if you notice signs of an allergic reaction like hives, difficulty breathing, swelling of your face, lips, tongue, or throat.

This is not a full record of all possible side effects. If you mark other effects not listed above, contact your doctor or pharmacist.

What are the precautions while using Melatonin?

See also warning section.

Do not drive or operate machinery within five hours of taking the supplement, as melatonin can cause daytime drowsiness.

It is not recommended to use melatonin in some people including those with epilepsy, autoimmune diseases, or taking warfarin. Caffeine and fluvoxamine may elevate plasma concentrations of melatonin. Melatonin may decrease plasma concentrations of nifedipine.

After taking melatonin, avoid activities that expose you to “blue light” such as watching television or using the smartphone. Blue light may cause your body to produce less melatonin because of the brightness of the screens. Thereby making it less effective.

Avoid using alcohol along with this supplement as melatonin supplements are time-release (they take some time to begin working). Having an alcoholic drink hinders this process and can make the supplement not work effectively.

Melatonin is not safe to use in pregnancy, so avoid using it. It may also interfere with ovulation, making it more difficult to become pregnant.

It is not known whether melatonin passes into breast milk or could harm a breastfeeding baby. You should not take this supplement while breastfeeding without talking to your doctor first.

What are the drug interactions of Melatonin?

Major Interaction:

CNS depressants (sedative medicine) such as clonazepam, lorazepam, phenobarbital, zolpidem, and others may interact with melatonin causes an addictive sedative effect (too much sleepiness). Avoid taking this combination.

Moderate Interaction:

Be cautious with these combinations:

Fluvoxamine (selective serotonin reuptake inhibitor): This drug increase melatonin level thereby increasing the effects and side effects of melatonin.

Antiepileptic drugs (seizure threshold lowering drugs): Taking melatonin with these drugs might increase the risk of seizures.

Antidiabetic drugs: Melatonin may interact with antidiabetic medications such as glimepiride, glyburide, insulin, pioglitazone, rosiglitazone, chlorpropamide, glipizide, tolbutamide, and others. Melatonin might decrease the effectiveness of diabetes drugs by increasing blood sugar levels.

Immunosuppressants: Melatonin might stimulate the immune system and interfere with immunosuppressive therapy. Melatonin decrease the effectiveness of medications that decrease the immune system such as azathioprine, basiliximab, cyclosporine, daclizumab, prednisone, corticosteroids, and others.

Anticoagulants and antiplatelet drugs: Aspirin, clopidogrel, heparin, warfarin and others, these drugs reduce blood clotting. Combining the use of melatonin with them might increase the risk of bleeding.

Contraceptive drugs: Use of contraceptive pills along with melatonin supplement might increase the effects and possible side effects of melatonin.


See also precautions

Do not use melatonin in bleeding disorders as it makes this condition worse.

Avoid using melatonin in severe depression, as it may further worsen the symptoms of depression.

Monitor blood sugar level carefully in diabetic patients as melatonin might increase blood sugar level.

It is unsafe to use melatonin in blood pressure as it further raises blood pressure. Melatonin might increase the risk of having more seizure.

What are the forms and strengths of Melatonin?

Form: Tablet
Strengths: 1mg, 2mg, 3mg, 4mg, 5mg

Form: Extended-release tablet
Strengths: 3mg, 5mg

Form: Capsule
Strengths: 2.5mg

Form: Solution
Strengths: 0.25mg/mL, 1mg/mL

What is the dosage of Melatonin in adults/children?

Adults ( above 18 years):

For sleep disorders in blind people:

Take 0.5mg to 5mg of melatonin daily before bedtime up to 6 years. The maximum recommended dose is 10mg/day.

For trouble falling asleep:

0.3 to 5mg of melatonin daily before 30 minutes going to bed up to 9 months.

For sleep-wake cycle disturbances:

2-12mg of melatonin taken at bedtime for up to 4 weeks has been used.

For insomnia:

3-5mg every day orally at bedtime for up to 9 months.

For jet lag:

0.5-8mg orally at bedtime for 2 to 5 days. Low doses of 0.5-3mg are often used to avoid the side effects of the higher doses.

For benzodiazepine withdrawal with insomnia:

2mg controlled-release orally every day at bedtime for up to 6 months.

For cancer, adjunctive therapy:

10-50mg orally daily.

For a cluster headache, prevention:

10mg orally every day at bedtime.

For a migraine headache:

3mg orally every day at bedtime.

For nicotine withdrawal:

0.3mg orally 3.5 hours after stopping smoking.

For premedication for surgery:




For sleep disorders in blind children:

0.5-4mg of melatonin daily for up to 6 years.

For trouble falling asleep:

1-6mg of melatonin before bedtime for up to one month.

Sleep-wake cycle disturbances:

0.5-12mg of melatonin daily for up to 12 weeks.

For insomnia:

5mg or 0.05-0.15mg/kg of body weight taken at bedtime for up to 4 weeks in children 6-12 years. 6-9mg of melatonin in children with seizures 3-12 years.

For reducing anxiety before surgery:

0.05-0.5mg/kg of body weight in children 1-8 years.


TheMedPharma has made every effort to make sure that all the information is factually correct, comprehensive, and up-to-date. However, this website should not be considered as a substitute for the advice, knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or licensed health care professional before taking any medication. The drug information contained herein is subjected to changes if required. The lack of warnings or other information for a given drug does not mean that the drug or its combination is safe, effective or appropriate for use in all patients.