title: Narcotic blockade.
mesh_terms: D004361:Drug Tolerance; D005500:Follow-Up Studies; D003932:Heroin / Q000009:adverse effects*; D006801:Humans; D004091:Hydromorphone; D007275:Injections, Intravenous; D008691:Methadone / Q000008:administration & dosage* / Q000627:therapeutic use*; D009020:Morphine; D012046:Rehabilitation; D013375:Substance Withdrawal Syndrome / Q000188:drug therapy*; D019966:Substance-Related Disorders / Q000628:therapy*
chemical_list: D003932:Heroin; D009020:Morphine; D004091:Hydromorphone; D008691:Methadone