A psychoactive drug is a substance that affects the central nervous system and alters brain function. A psychoactive drug typically results in a temporary change in perception, consciousness, behaviour, and mood. A psychoactive drug can either be a prescribed medication or a substance that is used recreationally. Many psychoactive drugs are known to be habit forming and can cause dependence or addiction in certain individuals. Not all people who use a psychoactive drug however, will become dependent.
Psychoactive substances have been used for at least 10,000 years. In early history, psychoactive drugs were typically plant-based and often used for medicinal purposes. For example, chewing of the betel nut in Thailand dates back over 10,000 years ago, and chewing of coca leaves dates back at least 8,000 years amongst cultures in Peru. Native Americans were using tobacco long before European contact, and opiates made from the poppy plant have been used to control pain as early as 7,000 years ago.
Hallucinogens have been used for at least 2,000 years by various indigenous cultures. The use of psilocybin mushrooms dates back to the Mayans, and Native American cultures have used peyote in religious ceremonies for centuries.
The use of alcohol has been displayed by countless cultures since time began. In the 1840s, hashish was used to treat mental disorders at the Bicetre in France. Psychoactive drugs were introduced in medicine as early as the late-1700s. Since then, prescribed psychoactive drug use has continued to increase into what is seen today with modern medicine.
Psychoactive drugs are categorised into four different classes. These include:
A psychoactive drug is a substance that alters brain function and results in temporary changes in perception, mood, and behaviour.
Caffeine is the most widely used psychoactive drug in the world. It is known to excite the central nervous system and release pleasure-producing chemicals in the brain.
A psychoactive drug can be a legal or illicit substance that changes mood, consciousness, and thoughts. Legal psychoactive drugs can include prescription medication, caffeine, alcohol, and tobacco. Illicit psychoactive drugs can include cannabis, heroin, ecstasy, cocaine, and more.