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5-HYDROXY INDOLE ACETIC ACID (5-HIAA), URINE

Synonym(s):
Lab Section Category
View write-up
Specimen Required

​24 hr urine in 15 mL 50% HCl

Minimum aliquot volume : 30 mL urine

Total 24 hr urine volume must be clearly indicated

Method

​High Performance Liquid Chromatography

Reference Interval / Value

≥ 20 yrs: < 42.9 µmol/day

Turnaround Time

​Mean = 7 days, Range: 3 – 11 days

Day(s) Test Set up

​Monday - Friday

Remarks

Patient Preparation:

(1) Patient Should abstain from the following at least 3 days prior to and during urine specimen collection:


(a) intake of food which has high content of serotonin like vegetable food, bananas, pineapples, chocolate, walnuts, pecans, kiwi, fruit, plum and avocados


(b) where medically possible, drugs such as dihydrocaffein acid, p-Coumaric acid, ferulic acid and o-Hydroxybenzoic acid, drugs containing phenotiazines which may potentially interfere with the testing


(c) where medically possible, drug such as Guaifenesin, Glycerol guaiacolate, Mephenesin, Phenacetin, Acetaminophen, Methenamine,Phenothiazine Tranquilizers, Acetic Acid and Levodopa which may induce increase or decrease 5-HIAA production.

(2) If the patient cannot be completely removed from a drug regime, test result should be interpreted with appropriate clinical judgement based on expected physiology response to these drugs.

Change History Notes

  • 30 Mar 2020 09:00 AM

    ​Reference intervals and remarks have been updated on 30 Mar 2020

Back: Pathology Laboratory Services

Last Updated - 13 Jun 2025