Histamine, 24 Hour Urine


Specimen Collection Criteria

Collect: 24 hour urine sample with no preservative.

  • Keep 24 hour urine specimen iced or refrigerated during collection.
  • Include start and end dates and times for the collection period on the specimen container.
Urine Preservative Options
No Preservative
6N Hydrochloric Acid
Boric Acid (10g)
Sodium Carbonate
50% Acetic Acid

Physician Office/Drawsite Specimen Preparation

Maintain specimen refrigerated (2-8°C or 36-46°F) prior to transport.

Preparation for Courier Transport

Transport: Entire 24 hour urine collection, refrigerated (2-8°C or 36-46°F).

Rejection Criteria

  • Random urine specimens.
  • Specimens not collected and processed as indicated.


Ambient: Unacceptable
Refrigerated: 24 hours
Frozen: 2 weeks


Tuesday, Friday.
Results available in 3-11 days.

Reference Range

By report.

Test Methodology



Above-normal levels of histamine in plasma or urine are consistent with the diagnosis of mast cell activation occuring in patients with immediate hypersensitivity or mastocytosis.

Clinical Utility

Histamine is produced and stored in cytoplasmic granules in mast cells and basophils. Histamine is also foundin other cells, including parietal cells, enterochromaffin cells, endothelial cells, and platlets; and it mediates various biologic responses, including immediate hypersensitivity (bronchospasm, vasodilatation, and increased vascular permeability), gastric acid secretion, and tissue growth and repair. (1)

Evaluating patients for diseased of immediate hypersensitivity or mast cell proliferation (mastocytosis).

Above-normal levels of histamine in plasma and urine occur after allergen challenge in patients with immediate hypersensitivity and in patients with systemic mastocytosis.
Histamine appears in blood shortly after mast cell activation, but the levels may become undetectable within 60 minutes. Consequently, it may be preferable, depending on the time elapsedsince allergen exposure, to measure histamine in urine either in an aliquot from an acidified 24-hour urine collection or in a random urine specimen. (2)

Measurements of histamine in urine are subject to interference from histamine-rich foods, including cheese, wine, red meats, spinach, and tomatoes, and are not reliable in patients with urinary tract infections. (2) Histamine levels in blood and urine are suppressed in patients treated with antihistamine drugs. Patients should not have taken antihistamine drugs for 48 hours before testing.


  1. Church MK, Holgate ST, Shute JK, et al: Chapter 13, Mast cell derived mediators. In Allergy Principles and Practice Vol. I. Edited by E Middleton Jr, CE Reed, EF Ellis, et al. St. Louis, MO, Mosby Year Book, 1998, pp 146-167.
  2. Homburger HA: Methods in Laboratory Immunology. In Allergy Principles and Practice, Vol. I. 5th edition. Edited by E Middleton Jr, CE Reed, EF Ellis, et al. St. Louis, MO, Mosby Year Book, 1998, pp 417-429.

CPT Code


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