Inb4krokadil [spoiler]Krokadil is a cheaply made version of Desomorphine. (A derivative of morphine that is known for its quick onset of effects an relatively no nausea compared to morphine) Desomorphine can be easily synthesized with codeine as a precursor. Krokadil is the name for a specific version (popular in low income areas of Russia) of Desomorphine in which it is made without extracting toxic by products that are required to catalyze the chemical process. Because the manufacturers of Krokadil are most always addicts, they more are eager to use and less willing to take extra time to extract harmful byproducts. It is because of the harmful byproducts in this specific version of Desomorphine (iodine, phosphorus) that the "flesh-eating" factor exists.* Pharmaceutical-grade Desomorphine does not cause deterioration of flesh. Also, because Desomorphine is a derivative of morphine, which is a derivative of opium, vote for Heroin if you feel that this is the worst drug, seeing as Heroin is also a derivative of opium, and has similar affects, health affliction, and addiction potential. * [ https://www.erowid.org/chemicals/desomorphine/desomorphine_basics.shtml ][/spoiler] Just wondering. In my personal opinion, Heroin and Meth are the most unhealthy and addictive. Therefore I believe they're the worst. This thread broke my notifications [spoiler]Realizing that most people are in this thread are arguing about what constitutes as a drug, I'll say this. Caffeine is a drug, Tylenol is a drug, and even chocolate has theobromine which is sometimes considered an antitussive drug (cough suppressant)*, and is subject to a degree of addiction. My point is, drug is a very general term, and encompasses many medicines, supplements, foods, and drinks. Everything listed in the poll, including Marijuana and alcohol, is a drug. *[ http://m.fasebj.org/content/early/2005/01/27/fj.04-1990fje.full.pdf ] [/spoiler]