Concurrent Multiple Drug Use: Review and Implications

Abstract

Evidence supporting individual generalized tendencies to use psychoactive drugs is reviewed. As a given drug is used or abused more heavily, a wider range of other drugs tends to be used in concurrent patterns. Multiple drug use must enter our conceptions of abuse, as the acute and chronic consequences attributed to a given drug are often confounded by the concurrent use of other drugs. Indeed, the use of one drug may be a contributing cause of the use of others. Social policies directed toward intervention and prevention of single drugs must be reconsidered.