Is 10 mg of melatonin too much
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Is 10 mg of Melatonin Too Much?
Safety of High-Dose Melatonin
Melatonin is widely used for sleep disorders and jetlag, typically at low doses. However, the safety of higher doses, such as 10 mg, has been less documented. A systematic review and meta-analysis investigated the safety of high-dose melatonin (≥10 mg) in adults. The analysis included 79 studies with a total of 3,861 participants. The findings indicated that while melatonin did not significantly increase the risk of serious adverse events (SAEs) or withdrawals due to adverse events (AEs), it did increase the risk of minor AEs such as drowsiness, headache, and dizziness1. This suggests that while 10 mg of melatonin is generally safe, it may cause some mild side effects.
Toxicology of Chronic Melatonin Treatment
A randomized, double-blind clinical trial assessed the toxicology of 10 mg melatonin administered over 28 days to 40 volunteers. The study found no significant toxicological effects that would compromise the use of melatonin at this dose. The only notable effect was a reduction in stage 1 sleep, but no other differences were observed between the melatonin and placebo groups2. This supports the notion that 10 mg of melatonin is safe for short-term use.
Efficacy and Side Effects
In a study involving diabetic patients with coronary heart disease, 10 mg of melatonin administered daily for 12 weeks showed beneficial effects on various metabolic parameters, including reductions in oxidative stress markers and improvements in glycemic control. However, the study did not report significant adverse effects, further supporting the safety of this dosage4.
Performance and Mood Effects
Another study examined the effects of various doses of melatonin (10, 20, 40, or 80 mg) on mood and performance in healthy male volunteers. All doses, including 10 mg, significantly decreased oral temperature, increased self-reported fatigue, confusion, and sleepiness, and decreased performance in tasks requiring vigilance and reaction time5. This indicates that while 10 mg of melatonin is safe, it can affect mood and cognitive performance.
Pharmacokinetics and Sedation
A pharmacokinetic study of high-dose intravenous melatonin (10 mg and 100 mg) found no significant adverse effects, including sedation, when evaluated through simple reaction times6. This suggests that even at higher doses, melatonin does not induce severe sedation or other adverse effects.
Conclusion
Overall, 10 mg of melatonin appears to be safe for most adults, with minor side effects such as drowsiness, headache, and dizziness being the most commonly reported. While it can affect mood and cognitive performance, it does not pose significant toxicological risks. However, as with any supplement, it is advisable to consult with a healthcare provider before starting high-dose melatonin, especially for long-term use.
Sources and full results
Most relevant research papers on this topic
Safety of higher doses of melatonin in adults: A systematic review and meta‐analysis
Higher doses of melatonin in adults appear to have a good safety profile, but may increase the risk of drowsiness, headache, and dizziness.
Meta-Analysis
Highly CitedRandomized, double‐blind clinical trial, controlled with placebo, of the toxicology of chronic melatonin treatment
Chronic melatonin treatment at 10 mg for 28 days showed no toxicological effects, as assessed by polysomnography and laboratory tests.
RCTHighly CitedLow, but not high, doses of melatonin entrained a free-running blind person with a long circadian period
Low doses of melatonin can entrain a blind person with a long circadian period, but high doses do not, suggesting that too much melatonin may spill over onto the wrong zone of the melatonin phase-response curve.
Highly CitedMelatonin administration lowers biomarkers of oxidative stress and cardio-metabolic risk in type 2 diabetic patients with coronary heart disease: A randomized, double-blind, placebo-controlled trial.
Melatonin supplementation significantly improves metabolic health and reduces oxidative stress in type 2 diabetic patients with coronary heart disease.
RCT
Very Rigorous JournalHighly CitedEffect of pharmacological daytime doses of melatonin on human mood and performance
Daytime doses of melatonin can decrease oral temperature, auditory vigilance, reaction time, and self-reported vigor, while increasing fatigue, confusion, and sleepiness.
RCT
Rigorous JournalHighly CitedPharmacokinetics of high‐dose intravenous melatonin in humans
High-dose intravenous melatonin does not induce sedation and no adverse effects were reported in this study.
RCTRigorous JournalMelatonin for sleep disorders in children
A dose of 10.5 mg daily for a 612-year-old child with autistic spectrum disorder is unlikely to cause significant harm, as melatonin has not been shown to cause severe adverse effects at a wide range of doses.
Optimal Melatonin Dose in Older Adults: A Clinical Review of the Literature.
Melatonin doses between 1 mg and 6 mg are effective for improving sleep in older adults, but further studies are needed to determine the optimal minimum effective dose.
Systematic ReviewA double-blind, placebo-controlled intervention trial of 3 and 10 mg sublingual melatonin for post-concussion syndrome in youths (PLAYGAME): study protocol for a randomized controlled trial
Sublingual melatonin treatment (3 or 10 mg) for 28 days may improve post-concussion syndrome symptoms in youths with mild traumatic brain injury.
RCTVery Rigorous JournalMelatonin pharmacokinetics following two different oral surge‐sustained release doses in older adults
Melatonin pharmacokinetics remain linear in older adults, with both low-dose and high-dose doses maintaining elevated levels beyond the typical sleep period.
RCTHighly Cited