What the clinician needs to know about magic mushrooms

Psilocybe semilanceata, commonly known as the 'liberty cap' mushroom, is a small, creamy-yellow or brown fungus (5–15 mm across) that grows naturally in dark, damp areas of the UK, especially after heavy rainfall from September to November. Its consumption for hallucinogenic effects has a long history in ritual ceremonies, notably in Mexico. In the UK, it is the most commonly used psychedelic mushroom species, while a closely related type is used in the USA.

Study at a glance

Abstract

This term refers to mushrooms that grow naturally and have hallucinogenic (sometimes called psychedelic) properties. Consumption of different species has occurred in various cultures over the centuries, with use in ritual ceremonies in Mexico being particularly well known. In the UK at present the species most commonly used is Psilocybe semilanceata , also known as the ‘liberty cap’ mushroom. This grows in many areas, particularly in dark places and after heavy rainfall, with fruition occurring from September to November. It is creamy-yellow or brown in colour, very small (5–15 mm across) with a thin fragile stalk. In the USA a closely related type is used.