Acid - LSD (d-lysergic acid diethylamide)
LSD is one of the most commonly used 'psychedelic' or 'hallucinogenic' substance. It comes in a variety of forms, but is virtually always taken orally. Today, LSD is most commonly found in the form of small squares of paper called blotter (full sheets of paper are decorated with artwork or designs, perforated, then soaked in liquid LSD solution and dried). Other forms include, pills, gelatin sheets or shapes (pyramids, cubes, etc), liquid, liquid sugar cubes, and powder. Blotter is most common because it is easily produced, easily concealable and the format allows for few adulterant chemicals.