Endorsed drugs today include caffeine and sugar (to keep you energized and productive at work), nicotine (to help you cope with the stress-levels induced by being high on sugar and caffeine all the time) and alcohol (to help you release the pent up tension from work and help you forget how shitty your life is). Banned drugs include Cocaine (more profitable to traffic it when it's illegal), Marijuana (which threatens a lot of established cartels in pharmacology and medicine. It also makes you less likely to work very hard, especially when also realizing that the work is not worth doing) and hallucinogens like LSD, mushrooms etc. (which dissolve ordinary social conditioning and support values antagonistic to the establishment).