title: Problems in testing for abused drugs.
mesh_terms: D006801:Humans; D013287:Illicit Drugs / Q000652:urine*; D008722:Methods; D004364:Pharmaceutical Preparations / Q000652:urine*; D019966:Substance-Related Disorders / Q000175:diagnosis* / Q000652:urine
chemical_list: D013287:Illicit Drugs; D004364:Pharmaceutical Preparations