What Is Alpha-Gal Syndrome?

Updated on Tuesday, March 12, 2019

Atlanta Allergy & Asthma News

Alpha-gal syndrome is a type of food allergy to red meat which includes beef, pork, lamb, or even sea mammals. Most people who develop alpha-gal syndrome in the U.S. develop the condition after a Lone Star tick bites them. The Lone Star tick transmits a sugar molecule called alpha-gal into the body and in some people, this triggers an immune system reaction that later produces allergic reactions when they eat red meat. Reactions can vary in severity and often take hours to develop, whereas allergic reactions to other foods usually develop immediately. This delay has led to difficulty in connecting the food to the reaction and why researchers believe the condition was overlooked until recent years.

Reactions to alpha-gal syndrome may vary, and the severity of each reaction is unpredictable. People may not always experience the same symptoms during each reaction due to the amount of the allergen they are ingesting.

Symptoms include:

  • urticaria (hives)
  • swelling of the face, lips, tongue or other body parts
  • nausea
  • stomach cramps
  • indigestion
  • vomiting
  • diarrhea
  • sneezing
  • headaches
  • in severe cases, death from anaphylaxis

People who have unexplained allergic reactions, and who test negative for other food allergies, may be affected by alpha-gal syndrome. An expert evaluation by an allergist familiar with this condition is recommended. There's no treatment other than avoiding red meat and patients should always carry an epinephrine auto-injector.

The lone star tick is found predominantly in the southeastern U.S. and most cases occur in this region. The key to preventing this allergy to red meat is avoiding tick bites. Apply insect repellent when in wooded, grassy areas and wear long pants and long-sleeved shirts. Always perform a thorough, full-body tick check after spending time outside. The U.S. Centers for Disease Control and Prevention states that the risk of getting bitten by the Lone Star tick is highest in the early spring and late fall.