14.1.1  Why do people initiate substance use?

There are many reasons why people start to use and continue to use substances. The substances may be taken to reduce stress and alleviate pain, or alternatively to stay alert, to stimulate the mind in order to study or to better perform some task, or simply to have fun with friends. People with mental health problems may take substances to ‘treat’ symptoms (although you should recall from Study Session 13 that this is very unwise because it can aggravate symptoms and limit the effectiveness of antipsychotic medication).

Some disadvantaged members of the community (for example, people who are unemployed or youth out of school) may use substances to occupy their time. Young people often initiate drug use out of curiosity or because of peer pressure. You may be wondering why people continue to use substances. After repeated drug use, ‘deciding’ to use substances is no longer voluntary because the substances induce changes in brain function, which leads to addiction (Figure 14.1).

Process of development of addiction in the brain
Figure 14.1  Process of development of addiction: voluntary use induces changes in brain processes, which in turn lead to addiction.

14.1  Substance use problems

14.1.2  How substances affect the brain