When I was suffering from insomnia, I was so exhausted and nothing was working. I got tired of it and decided to OD on one and a half (1 ½) bottles of sleeping pills. That's A LOT of fucking pills. Needless to say, I survived, and didn't even have to go to the hospital or anything. Just a really bad headache and feeling overall like shit for about a week. I did sleep that night though lol
Bottom line is, I don't think it's effective, really. You'd probably have to take an insane amount, but I doubt it would be very pleasant.