reference
Histamine
Rapid mast cell and basophil mediator for vascular leak, itch, mucus, and smooth muscle effects
mast cellbasophilitchvascular leak
Review layer
Last reviewed 2026-05-17
conceptualeducational
Systems teaching draft. Content is structured for education and graph expansion, with formal source tagging ready for the next review pass.
secreted-molecule
Systems Context
Histamine marks the fast layer of mast cell biology; delayed symptoms usually require lipid mediators and cytokines too.
Clinical Use
Explains rapid wheal, flare, itch, flushing, rhinitis, and parts of bronchospasm.