Abstract
The main purpose of this study was to draw up literature about polydrug misuse and to study the patterns and gender differences of polydrug misuse in a sample (N= 1,268) of narcotics users in Sweden. They were interviewed personally when entering treatment about their drug misuse from debut to established misuse. A nationwide case-finding study was used to verify the results. First, results indicate that those studied were primarily polydrug misusers and that alcohol consumption was very high. Second, gender differences were found. Third, a basic characteristic of multiple substance use was formulated. The findings are discussed in relation to new knowledge of consumption patterns.