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melatonin

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Brand names: Melatonin

Hormone Supplement (Sleep Aid) OTC

Melatonin is a hormone supplement that can help with sleep. You should take it 15 minutes before eating.

What it does

This medicine is used to help with sleep problems.

Common side effects

Tiredness, Nausea, Diarrhea

Key warnings

There are no boxed warnings for this medication.

How It Works

Melatonin is a hormone that your brain makes. It helps control your sleep and wake cycles. Taking this medicine adds more melatonin to your body.

How to Take It

Take 20 drops in a little water. Do this two times per day, 15 minutes before you eat. Follow your doctor's instructions about how much to take. Do not take more than your doctor tells you to.

Pregnancy & Breastfeeding

It is not known if this medicine is safe to take during pregnancy or while breastfeeding. Talk to your doctor before taking it if you are pregnant or breastfeeding.

Missed Dose

If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and take your next dose at the regular time.

Storage

Store at room temperature away from heat and moisture.

Side Effects (from patient reports)

Based on 29,122 FDA adverse event reports.

Tiredness
4,195
Feeling sick to your stomach
3,592
Using the medicine for something it is not approved for
3,225
The medicine is not working
3,031
Loose stools
2,865
Head pain
2,797
Difficulty breathing
2,437
Trouble sleeping
2,428
Accidental fall
2,301
Aches
2,251

FDA Adverse Event Report Analysis

Detailed analysis of 51,370 reports from the FDA Adverse Event Reporting System (FAERS). Reports span 2004–2025.

Total Reports

51,370

Death-Related Reports

4,506

Hospitalization Reports

17,241

Top Indication

Product Used For Unknown Indication

Gender Distribution

Female 28,004 (59%)
Male 19,382 (41%)

Age Distribution

0–17 4,820
18–44 5,859
45–64 9,463
65–74 7,011
75+ 7,163

Most Reported Adverse Reactions (FAERS)

# Reaction Reports
1 FATIGUE 4,196
2 NAUSEA 3,592
3 OFF LABEL USE 3,225
4 DRUG INEFFECTIVE 3,031
5 DIARRHOEA 2,866
6 HEADACHE 2,798
7 DYSPNOEA 2,436
8 INSOMNIA 2,429
9 FALL 2,301
10 PAIN 2,252
11 DIZZINESS 2,219
12 VOMITING 2,123
13 DEATH 2,032
14 SOMNOLENCE 1,842
15 ASTHENIA 1,818

Reactions in Death Reports

DEATH 2,028
OFF LABEL USE 397
SEPSIS 361
NAUSEA 343
GENERAL PHYSICAL HEALTH DETERIORATION 329
MULTIPLE ORGAN DYSFUNCTION SYNDROME 328
VOMITING 318
COMPLETED SUICIDE 310
CONSTIPATION 303
ABDOMINAL PAIN 291

Reactions in Hospitalization Reports

FALL 1,330
PNEUMONIA 1,273
DYSPNOEA 1,256
NAUSEA 1,186
FATIGUE 1,145
OFF LABEL USE 1,139
VOMITING 988
DIARRHOEA 960
SOMNOLENCE 847
ASTHENIA 789

Source: FDA FAERS (Adverse Event Reporting System) FDA FAERS (Adverse Event Reporting System) Reports are voluntary and do not establish causation

Serious Warnings

There are no boxed warnings for this medication.

Known Drug Interactions

From a pharmacokinetic perspective, no dose adjustment for drugs that are substrates of CYP1A2 (e.g., theophylline, duloxetine, melatonin), CYP2D6 (e.g., atomoxetine, desipramine, venlafaxine), CYP2C19 (e.g., omeprazole, lansoprazole, clobazam), and CYP3A4 (e.g., midazolam, pimozide, simvastatin) is necessary when VYVANSE is co-administered [see Clinical Pharmacology (12.3) ] .

Mechanism: Lisdexamfetamine does not change how the body's enzymes break down melatonin.

What to do: No dose adjustment is required when using these two products together.

7.3 Beta-Adrenergic Receptor Antagonists (e.g., acebutolol, metoprolol) Beta-adrenergic receptor antagonists have been shown to reduce the production of melatonin via specific inhibition of beta-1 adrenergic receptors.

Mechanism: Both of these products target the same sleep receptors in your brain. Using them together could cause excessive sleepiness or change how the prescription medicine works.

What to do: Talk to your doctor before taking over-the-counter melatonin with this prescription sleep medicine. They may advise you to avoid using both at the same time.

Common Questions

What is this medicine for?
It is used to help with sleep problems.
How should I take this medicine?
Take 20 drops in a little water, two times per day, 15 minutes before meals.
What should I do if I miss a dose?
Take it as soon as you remember. If it is almost time for your next dose, skip the missed dose.
Can I take this medicine if I am pregnant?
Talk to your doctor before taking it if you are pregnant.
Can I take this medicine if I am breastfeeding?
Talk to your doctor before taking it if you are breastfeeding.
What are the side effects of this medicine?
Common side effects include tiredness, nausea, diarrhea, headache, and dizziness.
Can I take more than the recommended dose?
No, do not take more than your doctor tells you to.
How should I store this medicine?
Store at room temperature away from heat and moisture.
Can I drive or operate machinery while taking this medicine?
This medicine may make you sleepy. Be careful driving or operating machinery until you know how it affects you.
What should I do if I have a serious side effect?
Call your doctor right away if you have any serious side effects.
What are the common side effects of melatonin?
The most commonly reported side effects of melatonin include Tiredness, Nausea, Diarrhea, Headache, Dizziness. Based on 29,122 FDA adverse event reports. Always consult your healthcare provider about potential side effects.
Does melatonin interact with other medications?
Yes, melatonin has 2 known drug interactions. Notable interactions include lisdexamfetamine, tasimelteon. Always inform your doctor about all medications you are taking.
What drug class is melatonin?
melatonin belongs to the Hormone Supplement (Sleep Aid) drug class. It is available over the counter (OTC). This medicine is used to help with sleep problems.
Is melatonin safe during pregnancy?
It is not known if this medicine is safe to take during pregnancy or while breastfeeding. Talk to your doctor before taking it if you are pregnant or breastfeeding. Always consult your healthcare provider before using any medication during pregnancy or breastfeeding.

Related Medications in Hormone Supplement (Sleep Aid)

Other drugs grouped near melatonin — same-class peers and common alternatives.

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Medication Guides

Related Health & Safety Data

What the FDA Data Shows for melatonin

The FDA label for melatonin (sold under brand names such as Melatonin) classifies it as an over-the-counter product in the Hormone Supplement (Sleep Aid) class. This medicine is used to help with sleep problems. Official labeling lists 5 commonly reported side effects, including Tiredness, Nausea, Diarrhea.

Post-market surveillance from the FDA Adverse Event Reporting System (FAERS) captures real-world experience. For this drug, FAERS contains 29,122 voluntary reports. The database also lists 2 documented drug interactions derived from FDA labeling, with the top-flagged interaction rated minor severity. Acquisition-cost data is surveyed weekly by CMS and updated as manufacturers report changes.

Report counts do not establish causation — a FAERS entry documents a temporal association, not proof that the drug produced the outcome. Widely prescribed medications naturally accumulate more reports than niche therapies, so raw totals must be interpreted alongside total exposure. Shortage status, recall history, and patent information further shape supply and switching decisions. This page summarizes public FDA data for educational purposes only and is not a substitute for professional medical advice — always consult a licensed healthcare provider before starting, stopping, or changing any medication.

Data Sources

Drug labeling: FDA Drug Labels (SPL/DailyMed). Adverse events: FDA Adverse Event Reporting System (FAERS).

FAERS reports are voluntary and do not establish causation. Drug interactions are derived from FDA labeling and clinical references. Always consult a healthcare professional before making medication decisions.

Last updated: December 22, 2018

All federal data sources used on this page