What is alpha-gal syndrome?

Alpha-gal syndrome is an allergy that causes your body to respond badly to eating meat from mammals and products made from mammals. Mammals are animals that have hair, such as cows, pigs, and deer. Symptoms usually start 2-6 hours after eating the mammalian meat or food.

Alpha-gal syndrome

What are the symptoms of alpha-gal syndrome?

Alpha-gal allergy can cause symptoms of the gastrointestinal (GI) tract (digestive system) like stomach pain, diarrhea (loose stool), nausea or upset belly, and vomiting (throwing up). It can also cause hives (an itchy rash), flushing of the skin, swelling of the face, or fainting.

Is there a test for alpha-gal syndrome?

Yes, there is a blood test that looks for immunoglobulin E antibodies (IgE) to alpha-gal. If you have these antibodies, you may have alpha-gal allergy. Your allergy and abdominal or stomach symptoms should get better when you stop eating mammalian meat to make the diagnosis.

What is the treatment?

The main treatment for alpha-gal allergy is to not eat foods that contain alpha-gal. This includes mammalian meat, fat and products made from them. Some patients who have this allergy also have symptoms from eating dairy products like cheese, butter, cream, and milk. Other people have problems eating gelatin, which is made from the bones of cows and pigs.

If I have alpha-gal syndrome, what foods from animals can I eat?

You can eat chicken, turkey, and fish, as these animals are not mammals.

How did I get this allergy?

In some people, a bite from certain ticks and tick larva sets off an immune response that causes the allergy. In the U.S., we believe that bites from the lone star tick cause most cases of the allergy. You might not see these bites, or they may look like chigger bites. Alpha-gal syndrome is different from Lyme disease, which is also caused by tick bites.

If I avoid more tick bites, could I "grow out" of the allergy?

Avoiding more tick bites is very important. In patients who do not get tick bites, the level of allergic antibodies to alpha-gal may go down over time and they may be able to eat red meat again. Checking for ticks on your body and bathing after being outdoors can help. Treating clothes and boots with permethrin, which kills ticks, can also help.

I ate beef last week and didn't have problems. Am I really allergic?

Unlike many other food allergies, alpha-gal allergy may not cause symptoms every time you eat mammalian meat or products. Fatter cuts of mammalian meat, drinking alcohol with meat and exercise can all make a reaction more likely. On the other hand, many things can cause GI symptoms and the antibody for alpha-gal is not a perfect test. Work with your health care professional to figure out if you have this allergy.

Are there medications that contain alpha-gal?

Yes. The cancer drug cetuximab, some pancreatic enzyme medications and gelatin capsules contain alpha-gal.

For more information on alpha-gal syndrome and GI symptoms, talk to your gastroenterologist.