mescaline /mes″kəlēn, -lin/ [Mex, mezcal] , a psychoactive agent with effects similar to LSD, this poisonous alkaloid is derived from a colorless alkaline oil in the flowering heads of the cactus Lophophora williamsii. Closely related chemically to epinephrine, mescaline causes heart palpitations, diaphoresis, pupillary dilation, and anxiety. It is a Schedule I substance. The drug, taken in capsules or dissolved in a drink, produces visual hallucinations, such as color patterns and spatial distortions, but it does not ordinarily induce disorientation. Mescaline is used in some religious ceremonies to produce euphoria and a feeling of ecstasy. Also called peyote.
