A psychoactive substance is a chemical compound which crosses the blood–brain barrier and acts primarily upon the central nervous system where it affects brain function, resulting in 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 to purposefully alter one's consciousness, as entheogens for ritual, spiritual, or shamanic purposes or as tools for studying or augmenting the mind. Many psychoactive drugs have therapeutic utility, (e.g., anesthetics, analgesics or for the treatment of psychiatric disorders).
This index attempts to categorize and provide relevant, accurate and unbiased 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 effects in a comprehensive level of detail. This is done by following a standardized system of descriptions and terminologies that can be found within the subjective effects index.
Please see our summary index to view convenient and condensed versions of these articles.