While many drugs speed up or depress the central nervous system, there is a class of drugs that distorts how we feel, hear, see, smell, taste, and think. Called s because users often hallucinate, or experience nonexistent sensations, these drugs are also known as psychedelic, or mind-bending, drugs. Some hallucinogens come from natural sources; others are made in laboratories. Examples of natural hallucinogens are mescaline, psilocybin, DMT, and marijuana. Mescaline, which has been used by American Indians in religious ceremonies, comes fro ....