Tryptase is an enzyme stored and released mainly by mast cells. This blood test measures total tryptase in serum. Levels may rise temporarily following significant mast-cell activation or remain elevated in certain mast-cell disorders.
Used alongside symptoms and medical history to support evaluation after suspected anaphylaxis, establish a baseline in people with recurrent or severe allergic reactions, and help investigate mast-cell disorders such as systemic mastocytosis. It does not identify the specific substance responsible for an allergic reaction.