Hydroxy-5-Indole-Acetic Acid (5-HIAA) (24 Hr), Urine

Additional Info:
Test includes creatinine.

Useful For: Values above 10 mg/24 hours occur in carcinoid syndrome. Slight elevations also occur in nontropical sprue and after reserpine administration. Drugs which can interfere with testing due to physiologic response: Acetaminophen, alpha and beta blockers, atenolol, bromocriptine, broncholdilators, clonidine, digoxin, isoniazid, L-dopa, labetelol, methyldopa, monoamine oxidase inhibitors, nitroglycerin, sympathomimetic amines, phenobarbital, phenothiazines, phentolamine, reserprine, salicylates,
tricyclic antidepressants.

Methodology: High-Pressure Liquid Chromatography (HPLC)

Specimen Requirements: Submit an entire 24-hour urine collection in a urine container supplied by Meadville Medical Center Laboratory. Add 25 mL of 6N HCL as preservative at start of collection to maintain a pH of 3.0 or less. See “Urine Collection” section in front of manual for timed collection instructions. Refrigerate specimen during and after collection.


  • Patient should avoid food high in indoles such as avocado, banana, tomato, plum, walnut, pineapple, and eggplant. Patient should also avoid tobacco, tea, and coffee three days prior to collection.
  • Include patient’s age on requisition.

Analytical Time: 1 day

Days Set Up: Monday through Friday

CPT Information:
83497 – 5-HIAA
82570 – creatinine