Hallucinogens are a class of drugs that share an extensive history and have been used for spiritual and religious practices since the dawn of civilization. They are referenced in the Hindu holy book Rig Veda, the healing rituals of the Aztecs of pre-Columbian Mexico, and are often attributed to the illicit practices of those prosecuted in the Salem witch trials. The first synthetic hallucinogens were discovered by a Swiss chemist named Albert Hoffman in 1938 and were originally manufactured for psychiatrists to help their patients access repressed emotions. Other uses considered for early hallucinogens included ingestion by doctors to better understand schizophrenia patients and as an antibiotic. Their recreational use peaked in the 1960s, but began to decline after being declared illegal in 1966, except in Native American churches where hallucinogens continued to be used as a spiritual tool. Although their popularity is not as widespread as it had been in the "hippie movement", their use continues to be recorded among a minority of the school and college-aged population. Drugs considered to be in the hallucinogen category include LSD, mushrooms (psyilocybin), mescaline and N-Bomb. They can be smoked, made into liquor, injected, ingested, snorted, or even licked off the backs of some toads like the Sonoran Desert toad (Erowid.org). Some common "street names" for these substances include acid, blotter, sugar cubes, mushrooms, zoom, and angel dust. While some hallucinogens are synthetic, others, like peyote and salvia, are derived from plants and natural substances. Although hallucinogens are not physically addictive, users have the potential to become psychologically dependent and are therefore classified as...... middle of paper ......see >.United States. National Institute on Drug Abuse.DrugFacts: Hallucinogens - LSD, Peyote, Psilocybin and PCP. 2009. Unprinted. "."Information on LSD drugs." Narconon International. Narconon International. Internet. April 9, 2014. .Most, Albert. "Buffo Alvarius." The Vaults of Erowid. Erowid.org, March 18, 2009. Web. April 9 2014. “LSD Addiction.” LSD Addiction. April 9, 2014. United States. DrugFacts: Drug-Related Hospital Emergency Room Visits. 2009. Unprinted. .