I have in the past done a lot of psychoactive drugs: ecstasy. coke, amphetamines, cannabis, LSD, mescaline, ketamine, DMT, 2CB etc. They may not seem to cause many side effects in the short term, but they will impede your progress long term. The comedown will affect your mood, which in turn will affect the quality of your workouts. The impact on your health is pretty disastrous as well.
I very rarely use psychoactive drugs anymore as I find the impact on my system (both mental and physical) is just too high.