LSD or acid (lysergic acid diethylamide) is the most commonly used hallucinogen (also known as psychedelics). It is considered a typical hallucinogen causing similar effects to other hallucinogens like mescaline, psilocybin (mushrooms), and ibogaine. It became popular in the counterculture of the 1960s and 1970s, but since then its use has been limited to people in the Rave or club scenes.
It is usually taken by ingesting small tabs of paper (frequently placed under the tongue) which have been soaked in the liquid form of the drug then dried. In rare cases it is taken in a liquid, gelatin, or tablet form. Sometimes a dose is soaked into a sugarcube. Doses range from 20 to 100 micrograms now, though in the 1960s they ranged from 100 to 200 micrograms. Because LSD is produced illegally, it is difficult to know how strong a dose is. The effects of the drug begin in about 30 minutes and last up to 12 hours. It can be very difficult to sleep if LSD has been taken in the last 6 hours.