Quote Originally Posted by God v2.0
Melatonin is one of the brain chems that makes you feel tired, weed increases that by something like 3000% which is why you get really tired after you start to come down from smoking weed. Which is why a lot of people including myself use marijuana to get to sleep and maintain sleep longer without interruption.
actually what melatonin does is help your body to reset it's internal sleep schedule. exactly how it does this i'm not too sure about (try using the Submit A Question thing on a website @ www.holistichealthline.com), but alot of travellers use it when they're changing time zones constantly.