Alpha-gal allergy: What you need to know



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What is alpha-gal allergy?

  • Alpha-gal allergy is a condition more commonly known as red meat allergy. An alpha-gal allergy can cause a person to have anaphylactic and hypersensitivity reactions when they eat meat.
  • The term alpha-gal is short for galactose-alpha-1, 3-galactose, a carbohydrate molecule that can cause an allergic reaction in people with an alpha-gal allergy.
  • The molecule is found in the meat of mammals, including cows, sheep, venison, bison, and pigs.
  • Alpha-gal allergy is chiefly spread by the bite of the Lone Star tick, so named for the marking on its back.

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Causes of an alpha-gal allergy

Red Meat Allergy, Alpha-gal allergy: What you need to know
Alpha-gal may enter the body via a Lone Star tick bite.

Although Lone Star tick bites are not the only significant cause of alpha-gal allergies, they are estimated to be responsible for around 80 percent of cases.

Where are Lone Star ticks most common?

In the United States, the Lone Star tick is most common in Southeast Texas, Iowa, and New England. However, cases of the allergy have been noted in other parts of the country, including Hawaii, where the tick does not typically live.

When did alpha-gal start?

The alpha-gal allergy was only identified in 2006 and doctors are still learning about the condition. Cases of alpha-gal allergy are becoming increasingly common but are still considered rare.

When alpha-gal enters the body, via a tick bite or otherwise, the immune system produces antibodies to fight the molecule.

Allergy researcher Thomas Platts-Mills of the University of Virginia started studying the alpha-gal reaction in 2002 after discovering an allergic reaction to the cancer drug cetuximab.

Cetuximab contains the same alpha-gal sugar as meat, although the association was not made with tick bites until Platts-Mills himself was later bitten by ticks and developed the allergy.

It remains unclear exactly what substance in the tick’s saliva causes the development of alpha-gal antibodies.

What are the Signs and symptoms of alpha-gal syndrome?

Red Meat Allergy, Alpha-gal allergy: What you need to know
An alpha-gal allergy is often discovered after eating red meat.
Most people discover they have an alpha-gal allergy after eating red meat. However, they can also have a reaction after eating foods that contain gelatin or taking medications that use gelatin as a stabilizer.

Common symptoms of an alpha-gal allergy include:

  • stuffy or running nose
  • feeling nauseated
  • vomiting
  • sneezing
  • shortness of breath

An anaphylactic reaction restricts breathing and can be fatal, so it needs immediate medical treatment. Although rare, it has been known for people with an alpha-gal allergy to be admitted to the intensive care unit (ICU).

In some instances, it can take up to 4 to 6…