title: Epidemic patters of drug abuse.
mesh_terms: D003932:Heroin; D006556:Heroin Dependence / Q000453:epidemiology; D006801:Humans; D012959:Socioeconomic Factors; D019966:Substance-Related Disorders / Q000453:epidemiology*; D014481:United States
chemical_list: D003932:Heroin