The doctor has just gave me amitriptaline for a trapped nerve in my back and arm.. its an anti depressent.. nerve pain relief and helps you sleep.. people on coke will be taking it to help them sleep after there come down because when the cokes wearing off u feel really down and suicidal sometimes. And when you have a sleep you dont feel too bad. So it will be to get them sleep and not go on a downer after the coke wears off.. ill tell u how it works… imagine a scale of 1 to 10.. 10 u feel amazing.. 1 you feel down.. say you have a jammie doger biscuit u feel excited.. your brain releases endomorphins.. and u hit say 6 on the scale.. if you are going out fri night.. your excited again.. brain releases endos again and u hit say 6. . .. now.. u have coke you hit well over 10! Feel awsome and your using all your endomorphins the brain produces.. but when the coke wears off. U stop producing the endo morphins.. and you go to below 1.. which is were the downer comes from and people have commited suicide from this.. endomorphins is the chemical in your brain that makes you happy and sad.