Gameplayer.com.au has an interesting interview with the Australian tournament admin for the WCG on the topic of drug use in E-Sports.

Excerpt,
"In one WCG, a player I knew took amphetamines an hour before his match to boost his reflexes. His team ended up losing the match, although it certainly had an impact - his performance helped his team to win one map out of three - it kind of hits home that only the really talented will come out on top in the end."
The rest of the interview can be viewed here gameplayer.com.