I have a brother who is dying (liver) from drugs right now. he is an addict too. It has to do with the liver so the doctors say. It counteracts when alcohol is taken with cocaine or meth. It is not a for sure answer but it does answer why my brother is in the same situation as you son and what it does to my brother. All I can say is good luck to your son:). He desperately needs at 23 to stop his behavior and there is help out there for him but only if he truly wants it mind you. you cannot make him stop or get help. As a sister, I watched my brother destroy himself with drugs and to this day I am not quite sure if he is even alive in another state. I live aways from him but I hear of his abuse to himself and it saddens me. I had my own addiction of nicotine and now am no longer smoking and that was so difficult to stop I couldn’t imagine cocaine or meth. WOW! I found out that If i don’t stop smoking I would die by the time i was 40! So obviously I stopped and with health issues now myself, I keep remembering my brother and his issues and it makes it easier for me not to smoke anymore. It is mind over matter. I think the street drugs out there are so pure anymore that it will just kill you. I again hope your son is and will get help before it is too late.