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 considered to have excellent safety profiles compared to most psychoactive substances. They are non-addictive and have low 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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