Alpha-gal syndrome is a tick-borne allergy to red meat caused by an immune response to the alpha-gal sugar. Symptoms include hives, diarrhea, and breathing difficulties hours after eating mammal meat.
The lone star tick is the primary vector, with cases rising as its range expands. Diagnosis involves blood tests and symptom history, and treatment includes avoiding trigger foods and using epinephrine or the drug Xolair.