What Is Alpha-gal Syndrome?
Alpha-gal syndrome (AGS) is caused when a carbohydrate known as galactose-α-1,3-galactose commonly referred to as alpha-gal is introduced into the body through the saliva of a tick, causing the body to develop an immune response.
- AGS is frequently described as a “red meat allergy” even though that label does not reflect the full condition.
- Because reactions differ from more typical food allergy reactions and symptoms often appear 2-6 hours after exposure, AGS is frequently misdiagnosed.
- It is estimated that as many as 450,000 people in the U.S. live with AGS.
- Legislation is being considered to recognize alpha-gal as the nation’s tenth major allergen.
Because alpha-gal syndrome can look so different from other food allergies, many patients spend years searching for answers.
Myth: It’s just a red meat allergy.
Fact: Alpha-gal syndrome is frequently described as a “red meat allergy,” but that label does not reflect the full scope of the condition. People with alpha-gal syndrome can react to any mammalian meat—including pork, lamb, and venison—as well as mammal-derived ingredients like dairy, gelatin, and certain medications. Pork is one of the most common triggers in alpha-gal syndrome. Because pork was framed as “the other white meat” in marketing campaigns, people don’t realize that pork is fully mammalian and contains alpha-gal. Pork can cause reactions as severe as beef.
Myth: Only people in the areas where lone star ticks live are at risk for developing alpha-gal syndrome.
Fact: Multiple tick species can cause alpha-gal syndrome. In the United States, the lone star tick is most often linked to the condition, but other ticks—including the black legged tick—have also been connected to cases.
Tick ranges are expanding driven by climate change, warmer winters, wildlife migration, and suburban sprawl. As a result, regions that historically never saw alpha-gal syndrome cases are now reporting them, catching clinicians and residents unprepared. Many people develop the condition outside of traditionally “high-risk” zones.




