( by Slavoj Kresak and Alan Biribo)
Mushrooms, the more obvious and conspicuous minority of fungi, have been for centuries hunted as agents of ecstasy and enlightment, from the exotic region of Mexico to the civilised, philosophical world of the Greeks. Even nowadays, it is very popular to search for the so called "magic mushrooms" (a favourite pastime of hippies).
"Magic mushroom" is the layman's term for mushrooms belonging to the genus Psilocybe which is Greek for naked head. This genus contains the majority of hallucinogenic species. It is currently in need of further taxonomy to distinguish closly related species.
P. semilanceata and P. penranlosa are both common species that have relatively low potency. Twenty to forty mushrooms will cause a mild intoxication. Some species such as P.cubensis and P. cynascens have a low potency but are less common. Rare P. strictipes and P. baeocystis are very potent and occasionally lead to an overdose when confused with P. semilanceata. Two specimens of P. baeocystis and four of P. strictipescan are effective doses.
The toxin responsible for the euphoric nature of this genus is psilocybin/psilosin or baeocystin. The psychomimetic effects of mascaline, LSD, and these toxins are similar. The duration of psilocybin and psilosin intoxication is shorter than for either LSD or mascaline. The dosage for psilocybin/psilosin is 6-20 mg. LSD is 120-150 times more powerful, and mascaline about an order of magnitude less potent. Evidence of cross tolerance among the three drugs indicates that their psychic effect is due to the same mechanism of action in the brain. Overall, psilosin tends to inhibit the parasympathetic hormone serotonin.
Following the ingestion of Psilocybe mushrooms, symptoms resembling those induced by LSD begin in about 30-60 mins and continue for several hours. The consumer displays anxiety and difficulty in concentration and understanding. At the same time changes in sensory preception as well as changes in size, shape, color, and depth of vision occur. The mood is usually elevated, but depression may follow.