Test Catalog Search Home Test Catalog Search Testing Choices: From the standard to the extraordinary × Search Clear Filter by: Clear all Method(s) Enzyme-Linked Immunosorbent Assay (ELISA) (1) Gas Chromatography (GC) (2) Headspace Gas Chromatography (GC) (1) (-) High Performance Liquid Chromatography/ Tandem Mass Spectrometry (LC-MS/MS) (1) Sample Type (-) Blood (1) Serum or Plasma (1) Urine (1) Test Area Drugs of Abuse (1) Test Category Analgesics (3) Anticholinergics (1) Antihistamines (1) Antihypertensives (1) Antimicrobials (1) Antipsychotics (2) (-) Depressants (1) Hypoglycemic Agents (1) Test Sub-Category Opiates/Opioids (1) Test Test Name 2276B Heroin Metabolites - Free (Unconjugated), Blood