Histamine, Plasma Unit Converter

Histamine is a chemical messenger produced by mast cells and basophils throughout the body. It plays a central role in immune responses, allergic reactions, stomach acid production, and neurotransmission.

A plasma histamine test measures the amount of histamine circulating in the blood. It is most often used to evaluate suspected anaphylaxis, mast cell disorders, or other conditions involving abnormal histamine release.

Because plasma histamine levels rise within minutes of an allergic reaction and return to baseline within 30 to 60 minutes, the timing of the blood draw is critical for accurate results.

Histamine is produced and stored primarily in mast cells and basophils found throughout the body, with high concentrations in the skin, lungs, and gastrointestinal tract. It is synthesized from the amino acid histidine by the enzyme histidine decarboxylase.