It's hard to say exactly how much melatonin is too much since there is no standardized ... but taking more than 10 mg can cause side effects, like daytime drowsiness and headaches.

Dr. Warner's go-to is Symphony Natural Health's 0.3 mg Plant Melatonin. Supplementing with too much can backfire. "If you ...

Lower doses often work as well as higher doses, if not better. In most cases, 10 mg of melatonin is too much melatonin. This high dose will often lead to blood levels much higher than are natural.