What Patients Should Know About Alpha-Gal Allergies

The most common foods that cause allergic reactions in people are milk, egg, fish, wheat, shellfish, tree nuts, peanuts, and soybeans. However, there have been reports of allergic reactions to many other types of foods, including red meat. Research shows that for a red meat allergy, unlike many food allergies, the cause can be connected to an environmental factor, a tick bite.

What is an Alpha-Gal Allergy?

Over the last decade, there has been an increase in the diagnosis of the alpha-gal allergy, also known as a red meat allergy, although it has likely been around longer. Alpha-gal is a sugar found in red meats, including beef, pork, venison, and lamb. A small percentage of adults and children have developed allergic reactions to red meat after being bitten by a tick who transferred alpha-gal to them.

Here’s a video of Dr. Turbyville discussing this allergy on Kentucky Afield:

What is alpha-gal?

Alpha-gal is a sugar that is found in the proteins of mammalian or red meat but not in humans.

What causes an alpha-gal allergy?

In the United States, this allergy has been primarily connected to the lone star tick. However, cases of alpha-gal has been found all over the world where other types of ticks, meaning the type of tick may not be a factor. When bitten the tick transfers the alpha-gal sugar to the person’s bloodstream, which lead to sensitization to alpha-gal in that person.

What are the symptoms of an alpha-gal allergy?

Alpha-gal patients often to have digestive symptoms, such as severe abdominal cramping, diarrhea, vomiting, along with skin symptoms like hives, itching, or flushing. Unlike most food allergies, these symptoms typically occur 3-6 hours after eating red meat. A delayed anaphylaxis reaction is also a risk for some patients, although reactions are more often mild.

How are alpha-gal allergies diagnosed?

If you suspect an allergy to meat, as with any food allergy, we recommend seeing a board-certified allergist. Due to the delayed nature of the symptoms it can be difficult to pinpoint the cause. Our physicians will start by taking a detailed patient history. Then we may use a combination of a skin test and an immunoglobulin E (IgE) blood test to confirm a diagnosis. This test measures the patient’s allergy antibody IgE levels to alpha-gal.

Is there a treatment for alpha-gal allergies?

Avoidance is the only option for patients with an alpha-gal allergy. There is no cure. It will be important to check ingredients of foods that may contain meat-based ingredients to avoid them. In case of accidental ingestion, we will prescribe an epinephrine auto-injector to use if the patient develops symptoms of anaphylaxis.

Is it a lifelong allergy?

While there is not option to treat this allergy with immunotherapy, it may go away if the patient avoids red meat. Our physicians can monitor the IgE blood test levels and help patients determine if it is possible to reintroduce red meat safely. However, many patients live with this allergy for years.

How can I prevent developing an alpha-gal allergy?

The main way to prevent this allergy is avoid tick bites. The CDC recommends using insect repellant, as well as wearing long sleeves and pants while outdoors in bushy or wooded areas. After returning indoors, it is important to check clothing and body for ticks. In this region, tick season often begins in March/April and lasts until temperatures drop below freezing.

If you are experiencing any of the symptoms above and have been bitten by a tick then it may be time to see an allergist. Visit our locations page to find an office near you.