If you use heroin, please remember that symptoms of heroin use are not pretty! Heroin use can cause discoloration, red/purple/black 'tracks' in the skin from ruined vessels, bad/rotting teeth, pustules on the face, and plenty of other unfortunate things like that. Also, withdrawal can kill someone who is addicted, and long-term rehabilitation is often needed. Usually the user has to be put on less dangerous substitites to the drug and tapered off of them altogether. In fact, many people going through heroin rehab end up addicted to the lesser forms of drugs used to try and unhook them.
If heroin does fit the bill! Good luck