Melatonin supplements are widely used to treat sleep disorders, post-traumatic brain injuries, and even migraines. While generally considered safe, taking excessive amounts can increase the risk of side effects. Life-threatening overdoses are rare, but potential harm exists, especially with long-term use or improper dosing. This article provides an overview of melatonin overdose risks, symptoms, and how to use it safely.
Understanding Melatonin Safety
Melatonin is non-toxic in moderate doses (under 5 milligrams) for short-term use. However, exceeding this amount or using it for extended periods can lead to unpleasant side effects. These include headaches, fatigue, dizziness, stomach upset, vivid dreams, and even bedwetting in children. More concerningly, melatonin can interact with certain medications and affect bodily processes like blood pressure and seizure thresholds.
Medication Interactions to Consider
Melatonin can interfere with the effectiveness of several medications:
- Blood thinners (Coumadin/warfarin)
- Antidepressants (Luvox/fluvoxamine)
- Antibiotics (Cipro/ciprofloxacin)
- Caffeine
- Oral birth control
- Immunosuppressants
Combining melatonin with alcohol or other sleep aids (kava, valerian, L-tryptophan) further increases the risk of adverse effects. Some studies suggest long-term melatonin use may even reduce semen quality, reinforcing the need for careful consideration.
Dosage Guidelines and Variability
There is no standard melatonin dose. Studies have used amounts ranging from 0.1 to 10 milligrams. Most experts recommend low to moderate doses (5-6 mg) as a safe and effective daily amount. Surprisingly, even 1 mg can be as effective as higher doses while minimizing overdose risk. It is best taken 30-60 minutes before bedtime.
Age-specific guidelines include:
- Infants (under 2): 1 mg
- Children (2-9): 2.5-3 mg
- Adolescents (10-17): 5 mg
- Adults (18+): 5-6 mg
- Children with special needs: 0.5-10 mg
Supplements often contain inconsistent melatonin levels, with some products exceeding label claims by as much as 478%. Always follow your healthcare provider’s recommendations and choose third-party tested brands.
Symptoms of Overdose and Emergency Care
Taking too much melatonin can cause:
- Excessive sleepiness
- Stomach upset
- Dizziness
- Fatigue
- Confusion
- Increased heart rate
- Skin irritation
- Hypothermia (body temperature below 95°F)
Severe symptoms requiring immediate medical attention include difficulty breathing, seizures, chest pain, tremors, and a sudden rise in blood pressure. Melatonin affects individuals differently based on age, dosage, and underlying health conditions. For example, even low doses (3 mg) have been linked to increased fracture risk in older adults.
What to Do in Case of Overdose
A melatonin overdose is rarely fatal. If you suspect an overdose, stop taking the supplement and consult a healthcare professional. Most side effects resolve once use is discontinued. If someone experiences irregular breathing or loses consciousness, seek emergency care immediately.
Long-term use exceeding 10 mg daily or longer than six months should only be done under medical supervision. Melatonin can be useful, but awareness of its risks and proper usage are essential for safe and effective supplementation.
