1.3Perspectives on Psychoactive Drugs

Psychoactive drugs affect mental processes and behaviours in a wide variety of ways. These effects, which result from the drug’s interaction with the central nervous system, cause alterations to consciousness, emotions, perception and behaviour in particular ways. In general these effects can be classed as depressant, stimulant or hallucinogenic.

Resource Kit for GP Trainers on Illicit Drug Issues

Part B2 AOD Background: Making Sense of Drug Use

Classes of psychoactive drugs

Depressants, stimulants and hallucinogens act on the central nervous system in different ways resulting in a variety of effects that share some common features.

•Depressants

Depressants are psychoactive drugs that interact with the central nervous system to produce major effects of decreasing consciousness, awareness and coordination.

•Stimulants

Stimulants are psychoactive drugs that interact with the central nervous system to produce major effects of increasing alertness and activity.

•Hallucinogens

Hallucinogens (sometimes called psychedelics) are psychoactive drugs that interact with the central nervous system to produce major effects of distorting perceptions and subjective awareness.

The table below outlines psychoactive drugs belonging to each class.

CLASSES OF PSYCHOACTIVE DRUGS

DEPRESSANTS / STIMULANTS / HALLUCINOGENS
Barbiturates
Alcohol
Benzodiazepines
Opioids
Solvents / Amphetamines
Nicotine
Cocaine
Caffeine
Volatile Nitrites / LSD
Psilocybin
(Magic Mushrooms)
Cannabis
MDMA (Ecstasy)

Classifying psychoactive drugs by their major effects has some limitations. Many drugs produce a range of behavioural effects, particularly at different dosages, in combination with other drugs, or when taken by different individuals. Alcohol consumption, for example, can increase activity in low doses (eg. talking) but is classified as a depressant as this is the major effect on behaviour and central nervous system function with significant levels of use. MDMA (Ecstasy) possesses some stimulant properties as the chemical structure and some physical effects are similar to amphetamines, and cannabis has some properties in common with the depressant class drugs.

Other aspects

There are many viewpoints from which we can examine psychoactive drugs. The following perspectives are of particular importance.

•Chemical –Each psychoactive drug is a unique chemical compound with a distinct arrangement of atoms. Their chemical structure, the processes involved with their manufacture, actions and reactions with other compounds can be investigated from a chemical perspective.

•Legal –Psychoactive drugs include a variety of substances that have legal restrictions that apply to them. They can be examined from the perspectives of the various legal sanctions that apply to their manufacture, possession, supply and use.

•Medical –Some psychoactive drugs are substances that have medical applications. The use of some psychoactive drugs also results in some conditions requiring medical intervention. They can be studied from the perspectives of their application for, and impacts on, the maintenance of health.

•Social –Psychoactive drugs are substances that are used in a range of social contexts for their effects on behaviour and mental processes. They can be considered from the perspective of their impact on social functioning and activity and the social contexts and rituals associated with their use. Whole areas of scientific and social investigation are devoted to these aspects of psychoactive drugs.

Reference:

Carmichael, C. 2001, The DISE Manual: A Resource Manual for Directions in Illicit Substance Education. QADREC, University of Queensland, Brisbane p.9

Resource Kit for GP Trainers on Illicit Drug Issues

Part B2 AOD Background: Making Sense of Drug Use