text: You correct in recognizing this as a dangerous habit. Isopropyl (rubbing) alcohol is quite toxic. When ingested your body breaks it down in to acetone, a chemical commonly found in nail polish remover. Clearly this is not safe. Your friend is abusing a substance. There are some commonalities in people who abuse substances. Primarily being that they are using the substance for an effect that aides them in escaping reality. Your Friend is a drug addict. He/she must desire to help himself/herself. You cannot force them into recovery no matter what you say, but this does not mean that you should not push your friend to seek help. Perhaps your friends does not know that treatment options are available. They are. The National Institute on Drug abuse has many paths that will help you to talk to your friend about the substance abuse as well as  centers for treatment. They can be found here: http://www.nida.nih.gov/