A psychoactive substance is a chemical substance, other than a nutrient or essential dietary ingredient, that affects brain function to produce alterations in sensation, perception, mood, consciousness, cognition, and behaviour.
Psychoactive substances are used for a number of purposes; for example, they can be taken recreationally for their euphoric and novel effects, as entheogens for ritual, spiritual, or shamanic purposes or as tools for probing or augmenting the mind. Many psychoactive substances have therapeutic utility and are used in routine medical practice (e.g. anaesthetics, analgesics, anxyiolytics, antidepressants, etc.).
This index attempts to categorize and provide relevant, accurate and neutral information regarding any and all psychoactive substances, with a particular focus on those which are useful as tools for exploring one's own conscious mind. The individual articles focus not just on detailing the chemistry, pharmacology, toxicity and harm potential of each substance, but also their subjective and experiential effects. This is done by following a standardized system of descriptions and terminologies that can be found in the subjective effects index.
Please see our summary index to view a convenient and condensed versions of each article.