Drugs Are Bad, mmmkay?
Except when terrible addictions to horrible drugs are Played for Laughs, often using a character who is Immune To Drugs.
These characters should be long since dead due to the vast amount of drugs and/or alcohol they take, but since their wacky antics must go on they rarely suffer any serious or lasting medical problems from them, aside from being insane, and quickly recover [...] [tvtropes.org]