Trading apples for oranges?: Results of an experiment on the effects of Heroin and Cocaine price changes on addicts' polydrug use

This paper studies polydrug use patterns in Heroin and Cocaine addicts from experiments measuring drug elasticities during changes in Heroin and Cocaine prices. Heroin addicts' demand for Heroin is inelastic; Cocaine, Marijuana, and Alcohol are complements, and Valium and Cigarettes are substitutes for Heroin. Heroin addicts' demand for Cocaine is inelastic; Marijuana and Valium are substitutes, and Alcohol is a complement. Cocaine addicts' demand for Cocaine is elastic; complements are Heroin and Alcohol, and substitutes are Marijuana and Valium. Cocaine addicts' demand for Heroin is inelastic; Alcohol is a complement while Cocaine, Marijuana and Valium are substitutes.