as said above it has to do with the chemicals interacting in your liver, I love drinking when I'm doing stimulants especially coke but sometimes if I'm doing a lot of stimulant I can't really drink a whole lot cause it makes me feel sick. If I'm basing coke you better believe I'm going to be drinking, whereas if I'm snorting it I have a harder time cause my throat/stomach is all numbed out and fucked up, alcohol definitely doesnt help. I used to like to drink on mdma but for some reason stopped liking it, now I only do it if I'm on a small amount of mdma and going out to a party or bar or something... Amphetamines with alcohol turn me into a raving loon, which I actually enjoy... Some of the craziest longest binges I ever went on involved 2-3 days of heavy amphetamine use and drinking throughout.