Test Catalog Search Home Test Catalog Search Testing Choices: From the standard to the extraordinary × Search Clear Filter by: Clear all Method(s) Enzymatic Assay (EZA) (1) (-) Gas Chromatography/Mass Spectrometry (GC/MS) (1) Sample Type Blood (1) (-) Fluid (1) Test Area Diagnostic Aids (1) Test Category Analgesics (2) Anesthetics (3) Antianxiety (1) Antiarrhythmics (1) Anticholinergics (2) Antidepressants (3) Benzodiazepines (1) (-) Biomarkers (1) Depressants (2) Muscle Relaxants (2) NPS/Designer Drugs (2) Plasticizers (1) Sedative/Hypnotics (4) Stimulants (1) Volatiles (1) Test Sub-Category Small Molecule (1) Test Test Name 0420FL Betahydroxybutyric Acid, Fluid