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Definition of hallucinogens
Last reviewed: 04.07.2025
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Hallucinogens are a class of drugs that cause psychotic-like symptoms (hallucinations, loss of reality, oneiroid states, and other dramatic changes in thought and perception). Among natural hallucinogens, the best known are psilocybin, found in mushrooms, and mescaline, found in the peyote cactus. Synthetic hallucinogens include lysergic acid diethylamide (LSD), as well as some tryptamine derivatives.
LSD is one of the most powerful hallucinogens (the average dose causing hallucinations is 1-2 mcg/kg). The effect begins 1 hour after use and lasts 8-12 hours. Hallucinations are most often visual, usually in the form of geometric shapes, less often auditory or tactile hallucinations occur. Mental changes are manifested by memory impairment, difficulty thinking, and mood lability. Physical dependence on LSD does not develop, but many people have psychological dependence.
Phencyclidine is a synthetic drug that causes primarily hallucinatory effects, as well as detachment, disorientation, body image disorder, nystagmus, sweating, tachycardia, and hypertension. The effects are dose-dependent. Overdose can be fatal. When treating, it should be taken into account that phencyclidine is excreted by the gastric mucosa, so the removal of the drug from the body can be accelerated by gastric lavage. The elimination of the drug from the blood can be accelerated by the introduction of solutions with a low pH, since phencyclidine has basic properties. Effective treatment should be accompanied by a decrease in urine pH to 5.5.