Introduction and aims: Multiple substance use leads to greater levels of psycho-behavioural problems, unsafe sex, and therefore a high risk of contracting sexually transmitted diseases, and is also more difficult to treat. This study aims to determine pattern of lifetime multiple substance use among Chinese heroin users before entering methadone maintenance treatment clinic.
Design and methods: A survey to obtain retrospective longitudinal data on lifetime multiple substance use was conducted among 203 heroin users in two of the biggest methadone maintenance clinics in Kunming City, Yunnan province.
Results: All participants used more than one substance in their lifetime. Most of them used four or more substance groups (range two to seven groups). The most common substance patterns in lifetime use were alcohol, tobacco, opiates and depressants. Approximately 80% of them had a history of simultaneous substance use (co-use). The most common combination of co-use pattern was heroin with depressant. Common reasons for co-use were to get high, to experiment, to sleep and to increase the potency of other drugs. Determinants of co-use were education, marital status and family relationship.
Discussion and conclusions: Multiple substance use is highly prevalent among Chinese heroin users. Depressants are the most common substances used in combination with heroin.