(Extract from the Mind Publication "Understanding the Psychological Effects of Street Drugs ")

There is a lot of concern about the increasing use of illegal or 'street' drugs, and their possible effects on physical and mental health. However, media information can often be inaccurate and sensationalised.

Research on illegal drugs tends to concentrate on chemical composition, and effects on laboratory animals. Few long-term studies on illegal drug users have been carried out. Because of society's attitudes to illegal drug users, truly objective studies are quite scarce.

At the same time the use of illegal drugs is now an unsensational part of youth culture, some research indicating that up to half of young people have experimented with illegal drugs or solvents by the time they leave school at 16.

The information given here concerns the general effects of street drugs on the mental health of all those who might use them. Specific issues concerning the use of street drugs by people with existing mental health problems - sometimes referred to as people who have 'dual diagnosis' - will be addressed in separate Mind publications.

Why do people start to use illegal drugs?

The main reason people start to use drugs and continue to use them is that they find the experience enjoyable. A number of factors may encourage people to start, including availability, curiosity, rebellion, peer influence and peer preference. But in most cases they are offered the opportunity by a friend they trust, who wants them to enjoy the same kind of experience they have had.

What are the patterns of drug use?

There are four discernible, but overlapping patterns of drug use. It is useful to bear in mind legal drug use (for example caffeine, alcohol, tobacco, medicines, and any others) when you read these explanations, as they are as applicable to legal drugs as they are to street drugs.

Abstinence - This means that a person is not taking a particular drug at the time. They may have never tried it, or they may have experimented with it and not liked it, or have used it regularly and stopped.

Experimentation - This means trying something out; it is usually a conscious decision, taking into account the influences pertaining at the time. Some people try some drugs a number of times before they decide whether they want to carry on using them or not. Some drugs (for example cannabis)  may have little effect the first time, which may make the person consider whether it is worth taking. Others may be unpleasant the first time (for example smoking cigarettes), and persistence may be required before the 'benefits' are realised. The majority of people who experiment with illegal drugs and solvents do not continue using them.

Casual/recreational/regular use - If a person decides to carry on using a particular drug, they may use it casually, recreationally or regularly. A casual drug user will use a particular drug when it is easily available, and not be too concerned when it is not, as well as not feeling they need it to enhance their enjoyment of situations.

A recreational user will use their drugs of choice for specific effects on specific occasions. Alcohol, caffeine and tobacco are used in a variety of circumstances for recreational reasons, as are, for example, cannabis, LSD and ecstasy. A regular user will take their drug(s) of choice most days, or (with some drugs), most weeks.

With most  drugs, each of these patterns of use may have undesirable effects on the individual. However, the great majority of drug users feel that their existence is enhanced by their drug use, and that they suffer no adverse consequences; they do not fall into the fourth pattern - problem drug use.

Dependent/problem/chaotic use - Recreational or regular use may slip into dependent, problem or chaotic use for a variety of reasons, which may be to do with the person, their situation, or the drug(s) they are using. A physical dependence may develop to some particular drugs, because after long-term regular use the body may require the drug in order to function normally. A psychological dependence may also develop with some drugs, making the person think they cannot function without them.

Problem drug use may involve adverse physical, social, legal, financial or mental health consequences. Chaotic drug use implies that obtaining and taking the drug(s) are the central and most important aspects of a person's life, and everything else is of little consequence.

This chaotic pattern is the least common by far, and may be reached a long time after experimentation - though for a very small number of individuals it can follow fairly quickly. People who are in this pattern of drug use are not necessarily stuck there, and may, with the appropriate motivation and support, return to other patterns.

Problem drug use may bring to the surface, reinforce or exacerbate existing or latent mental health problems. But cause and effect are difficult to separate in this situation, with the interaction of different factors on the drug-user complicating any assessment. Problem drug-use may include an element of self-medication; for example, taking amphetamines to increase confidence, anabolic steroids to change body image, or heroin to withdraw from an unpleasant reality.

Topics also included in this leaflet are: