I have a fair bit of experience with melatonin. Basically its a hormonal precursor that occurs naturally in the brain and leads to sleepiness (not a groggy/druggy sleepiness like most sleep aids, otc or script). You could think of it like Seratonins sleepy second cousin. Anyways the point is its all 'natural', and since its only a PRECURSOR, it is classified as a dietary supplement/vitamin (like that 5HTP stuff people take for various reasons) and can be purchased otc at any walmart or any store with a decent vitamin aisle. In no way were these habbit forming to me, and i only took them occasionally after i had a good sleep cycle down.
Tabs usually come in 300 mcg(MICROGRAMS) and i have found personally i only need about half that or less to obtain the desired results, be able to fall asleep and not be too groggy when i wake up. But these are one of those things that really affect everyone differently, so it may take a bit of experimenting to find your optimal dose. Also there is a chance these dont work for you, if that is the case and the tylenol pms DO work for you but you are worried about the liver, then i suggest buying the active sleep aid ingredient in tylenol pm, by itself. Since, afterall, its is the tylenol that is bad for your liver, and you dont even need the tylenol, u just want to sleeep! Anyways Tylenol PM active sleep ingredient is diphenhydramine, you can usually find that in the same aisle as tylenol pm and it goes by many generic names that usually have the word 'sleep' in it. These guys just got the sleep stuff, no tylenol or extra unneeded junk. Its also alot 'safer' without the tylenol. Just be careful cuz no matter how much johnson &johnson denies it this stuff CAN be habit forming, especially for an addict.