Alpha-gal syndrome is a tick-borne condition in which a sugar molecule called alpha-gal, present in mammals but not produced by humans and transmissible in the saliva of some ticks, can trigger delayed allergic reactions about 2â6 hours after a person consumes mammalian meat, producing hive-like rashes or anaphylaxis.
November 15, 2025
high
temporal
Definition, pathophysiology, and typical timing of allergic reaction
The Lone Star tick's saliva contains a sugar molecule called alpha-gal (galactose-alpha-1,3-galactose) that can induce antibodies causing allergic reactions to mammalian meats (for example, beef, pork, lamb, rabbit, venison) and mammalian-derived products (for example, milk, cheese, other dairy products, and gelatin).
high
biochemical
Mechanism by which tick exposure leads to food allergy