Updated September 03, 2013.

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Definition:

Psychoactive is a term that is applied to drugs or other substances that change a person's mental state by affecting the way the brain and nervous system work. This can lead to intoxication, which is often the main reason people choose to take psychoactive drugs.

In some situations, however, psychoactive drugs can be used to alter a person's mental state in order to exploit them, for example, with the use of date-rape drugs.

Psychiatric drugs, such as antidepressants, and drugs used to treat conditions such as ADHD, are also psychoactive. The psychoactive drug most commonly used to alter one's own or another person's mental state is alcohol.

Natural substances, such as hallucinogenic mushrooms, cacti, and the leaves, flowers and buds of certain plants may also be psychoactive. Some people perceive these psychoactive substances as more acceptable than manufactured drugs, because they occur naturally, but they can have a higher risk of overdose or poisoning due to the lack of control over the strength of the psychoactive and toxic components of the plant.

Pronunciation: sI-kO-ak-tiv

Also Known As: intoxicating

Alternate Spellings: psycho-active

Examples: Jeff became ill after eating a psychoactive mushroom that turned out to be poisonous.