Test Catalog Search Home Test Catalog Search Testing Choices: From the standard to the extraordinary × Search Clear Filter by: Clear all Method(s) (-) High Performance Liquid Chromatography/ Tandem Mass Spectrometry (LC-MS/MS) (3) Sample Type Blood (3) Serum or Plasma (3) (-) Urine (3) Test Area Therapeutics (3) Test Category Antihypertensives (3) Test Sub-Category (-) Alpha-2 Adrenergic Agonists (2) (-) Alpha-2 Adrenergic Antagonists (1) Beta Blockers (5) Calcium Channel Blockers (1) Diuretics (2) Other (2) Test Test Name 1275U Clonidine, Urine 2186U Guanfacine, Urine 4830U Yohimbine, Urine