Yes there are very anachronistic drug enforcement rules in use in chess. My point is that no chess player has ever gotten caught using performance enhancers, nor has any chess player admitted to using any of the legal drugs. There are a lot of cheaters in chess (http://en.wikipedia.org/wiki/Borislav_Ivanov), and if there was any mind enhancing drugs that used for chess I'm pretty sure they would be used by a lot of players, legal or not.