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) (1) Sample Type Serum or Plasma (1) Test Area Therapeutics (1) Test Category Antidiarrheals (2) Antiepileptics/Antiseizures (9) Antihistamines (5) Antipsychotics (5) (-) Dopamine Precursor (1) Hallucinogens (6) Immunosuppressants (4) Laxatives (1) Metals/Elements (6) Test Sub-Category (-) Parkinsons (1) Test Test Name 2504SP Levodopa, Serum/Plasma