Melatonin is a naturally occurring hormone that plays a role in regulating the body’s sleep-wake cycle. Many individuals use synthetic melatonin supplements as a sleep aid, often for occasional sleeplessness, jet lag, or shift work.
Understanding Melatonin
Melatonin is produced by the pineal gland, with levels increasing in the evening to prepare for sleep. This hormone synchronizes the body’s circadian rhythm. Supplemental melatonin is often used to assist individuals with sleep difficulties or adjusting to new time zones. While it promotes sleep, it is not a sedative.
Is Melatonin Overdose Possible?
While a fatal melatonin overdose is rare and not life-threatening like many prescription medications, taking excessive amounts can lead to undesirable effects. There is no universally agreed-upon lethal dose for melatonin, and very high doses have not been fatal in animal studies. An “overdose” in this context refers to consuming an amount significantly higher than recommended, resulting in adverse side effects. The exact amount varies by individual factors like age, weight, and sensitivity.
Recognizing Symptoms of Excessive Intake
Taking too much melatonin can disrupt the sleep-wake cycle and lead to uncomfortable symptoms. Common effects include excessive drowsiness, daytime tiredness, headaches, dizziness, and nausea. Other symptoms are stomach cramps, irritability, confusion, vivid dreams, or nightmares. Less common but more severe symptoms can include short-lasting depression, tremors, or significant blood pressure changes.
What to Do for Excessive Melatonin Intake
If you suspect excessive melatonin intake and experience adverse effects, stop taking the supplement. Most mild symptoms typically resolve as the body processes the excess. Rest and avoid activities requiring alertness, such as driving, for several hours.
For severe symptoms like difficulty breathing, seizures, or loss of consciousness, seek immediate medical attention. For less severe but worrying situations, contact a healthcare provider or poison control (1-800-222-1222 in the U.S.). If a child has taken too much, ensure they cannot access more and seek professional medical advice.
Safe Melatonin Supplement Use
To use melatonin responsibly, start with the lowest effective dose. For adults, this typically ranges from 0.5 mg to 3 mg, taken 30 to 60 minutes before bedtime. Doses over 5 mg often provide no additional sleep benefits and may increase side effects. Children generally require lower doses, starting from 0.2 mg to 0.5 mg.
Melatonin supplements are regulated as dietary supplements in the U.S., meaning they lack the strict oversight of prescription drugs, and labels may not accurately reflect content. Long-term continuous use is not extensively studied, so short-term use is recommended.
Melatonin can interact with medications like blood thinners, immunosuppressants, certain antidepressants, and drugs for blood pressure or diabetes. It can also increase sedative effects of alcohol and other central nervous system depressants. Individuals with pre-existing conditions like autoimmune diseases, seizure disorders, or depression should consult a healthcare professional.