The Beckley Foundation says
"Stimulants , Downers, Anti-psychotics and hallucinogens have a vast array of different effects, harms, benefits (and absolutely unrelated global legal classifications).
This guide classifies the family relationships and effects of 2CB, Mescaline, LSD, Nicotine, CBD, Opium, Diazepam, Alcohol, MDMA, Cocaine, Caffeine and a host of other licit and illicit substances besides, and can help us make informed decisions about which drugs to take when.
sources: http://www.informationisbeautiful.net/visualizations/drugs-world/