What happens if a person overdoses on melatonin?

If a person overdoses on melatonin, several symptoms and potential complications can arise. Here are the key points to consider:

Symptoms of Melatonin Overdose

• Excessive Sleepiness: This is one of the most common signs, especially in children, and can be severe enough to affect daily activities25.
• Headaches: A frequent side effect of taking too much melatonin135.
• Nausea and Vomiting: These gastrointestinal symptoms can occur, with repeated vomiting being a particular concern in children25.
• Dizziness: Dizziness is another common symptom associated with melatonin overdose134.
• Stomach Pain and Gastritis: Stomach inflammation and pain can result from high doses of melatonin4.
• Irritability and Mood Changes: Symptoms such as irritability, short-term depression, and mood problems can occur145.
• Slurred Speech: In severe cases, especially in children, slurred speech can be a sign of melatonin overdose2.
• Trouble Breathing: Although rare, difficulty breathing is a severe symptom that requires immediate medical attention5.

Severe Symptoms

• Life-Threatening Symptoms: While rare, especially in adults, severe symptoms include difficulty breathing, seizures, or a loss of consciousness. These require immediate emergency medical attention, such as calling 911 or visiting the emergency room125.

Recovery

• Reversibility: Melatonin does not last long in the body, with a half-life of 20 to 50 minutes. It is generally eliminated from the body within 4 to 5 hours. Stopping the supplementation immediately can help relieve symptoms4.

What to Do

• Seek Medical Help: If symptoms are severe or if you suspect a melatonin overdose, contact a poison control center or seek immediate medical attention. For life-threatening symptoms, call emergency services immediately125.

Special Considerations

• Children and Infants: Melatonin overdose can be particularly dangerous in children and infants. There has been an increase in melatonin-related poison control calls and hospitalizations among this age group15.
• Interactions with Other Substances: Ingesting melatonin along with other medications or alcohol can increase the risk of adverse reactions1.