Classical psychedelics (or classic psychedelics) refers to the most common, recognizable, and historically significant psychedelic substances. They generally include:
Classical psychedelics may be distinguished from novel psychedelics, which are generally psychedelics discovered after the 1970s. These include relatively older and well-tested substances like 2C-B as well as highly novel compounds like the 25x-NBOMe series, which were developed as neurochemical probes.
Furthermore, they are thought to have excellent safety profiles relative to most psychoactive substances, with low abuse potential and toxicity. However, adverse psychological reactions like severe anxiety, paranoia, delusions, mania, and psychosis are always possible, especially in individuals susceptible to mental disorders.
As a result, harm reduction practices are advised.
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