Overview

• Arizona State University and Yale researchers report that specialized intestinal mast cells drive reactions to ingested allergens by producing cysteinyl leukotrienes.
• In experimental models, the FDA‑approved asthma drug zileuton reduced symptoms and prevented the anaphylaxis‑linked drop in body temperature.
• Zileuton did not block reactions to allergens injected into the bloodstream, underscoring that gut-triggered anaphylaxis follows a distinct pathway.
• Detailed analyses show multiple gut mast‑cell subtypes primed by epithelial cues to make leukotrienes rather than histamine.
• The findings help explain why antihistamines often fall short in severe food-triggered events and highlight leukotriene‑targeting drugs, including montelukast, as repurposing candidates pending human studies.