Alpha-gal syndrome is a type of food allergy. It can happen after a tick bite. The allergy is to red meat and other products that come from mammals. Alpha-gal syndrome can be life-threatening.
In the United States, the condition most often begins with the bite of the lone star tick. Other types of ticks cause the condition in different parts of the world, mainly in parts of Europe, Australia, Asia, South Africa, and South and Central America.
Alpha-gal syndrome causes mild to intense allergies to red meat, such as beef, pork or lamb. It also can cause reactions to other foods that come from mammals, such as dairy products or gelatin.
Some people may have alpha-gal syndrome and not know it. There are people who have serious allergic reactions, called anaphylactic reactions, for no known reason. Because the reactions can be delayed for hours, researchers think that some of these people may be affected by alpha-gal syndrome.
The only treatment for alpha-gal syndrome is to not eat red meat or other products from mammals that can trigger reactions. A serious allergic reaction may need medicine called epinephrine and treatment in an emergency room.
An alpha-gal allergic reaction often starts about 2 to 6 hours after you eat something with the alpha-gal molecule.
Symptoms may be mild or lead to serious illness, and include:
Symptoms of alpha-gal syndrome may lessen or go away over time.
Get help if you have food allergy symptoms after you eat, even several hours after you eat. See your main healthcare professional or an allergy specialist, called an allergist.
Get emergency medical treatment if you have symptoms of a serious allergic reaction that causes trouble breathing, called anaphylaxis. Symptoms may include:
Most people with alpha-gal syndrome in the U.S. get the condition from lone star tick bites. Other types of ticks can cause the condition too, mainly in parts of Europe, Australia, Asia, South Africa, and South and Central America.
Experts think the ticks that cause alpha-gal syndrome carry alpha-gal molecules. When a tick that carries these molecules bites a human, the tick sends alpha-gal into the person's body. Experts don't know why some people have strong reactions to alpha-gal.
You're at higher risk if you live or spend time in areas that have ticks that carry alpha-gal. Having more than one tick bite seems to raise the risk even more.
Alpha-gal syndrome can cause a serious allergic reaction called anaphylaxis. It can be deadly without treatment. A prescription medicine called epinephrine treats anaphylaxis. You can give yourself a shot of epinephrine, also called adrenaline, with a device called an autoinjector (EpiPen, Auvi-Q, others). You also need to go to an emergency room.
Anaphylaxis symptoms can include:
Healthcare professionals think that some people who get anaphylaxis often and for no clear reason may be living with alpha-gal syndrome that hasn't been diagnosed.
Although it's rare, people with antibodies related to alpha-gal syndrome can have allergic reactions to certain medicines and vaccines. These may include the cancer medicine cetuximab (Erbitux). Talk to your healthcare professional before taking a new medicine or getting a vaccine.
The best way to prevent alpha-gal syndrome is to prevent tick bites. Stay away from areas where ticks live. Be careful in wooded, bushy areas with long grass. You can lower your risk of getting alpha-gal syndrome by following some simple tips:
To diagnose alpha-gal syndrome, a healthcare professional asks about your symptoms and your medical history and does an exam. A blood test can confirm that there are alpha-gal antibodies in your blood and measure the amount. But it's possible to have alpha-gal antibodies without having alpha-gal syndrome.
Alpha-gal syndrome treatment involves not eating the foods that cause your reaction. Always check the ingredient labels on store-bought foods. Make sure they don't have red meat or meat-based ingredients.
Ask your healthcare professional for a list of foods to not eat. These include meat extracts used in flavoring. The names of some meat-based ingredients make them easy to miss.
Be aware that some medical products made from animals may have alpha-gal. These might include heart valves from pigs and cows, lab-made proteins called monoclonal antibodies that fight diseases, the blood-thinning medicine heparin and some medicines to treat snake bites. But reactions to these products from people with alpha-gal syndrome are rare.
For a mild allergic reaction, an allergy medicine might help. For a more intense reaction, you may need a shot of epinephrine and emergency care. Many people with allergies carry a device called an epinephrine autoinjector. It's a syringe and needle that gives you a single dose of medicine when you press it against your thigh.
If you've been diagnosed with alpha-gal allergy, your healthcare professional is likely to prescribe an epinephrine autoinjector and teach you how to use it.
To keep from having an alpha-gal reaction, don't eat foods that have the following:
Check soup stock cubes, gravy packages and flavor ingredients in packaged products.
Be extra careful when you dine out. Even a small amount of meat can cause a serious reaction.
Do what you can to lower your risk. If you're worried that you may be allergic to something in a food, don't try it. Also think about bringing your own food to a party if guests are sharing a cooking surface to make food.
You may start by seeing your main healthcare professional. You may be sent to a specialist in allergies, called an allergist. Here are some tips to help you make the most of your appointment.
Take a family member or friend along if you can. Someone who's with you can help you gather information.
Make a list of:
Some questions to ask include:
Your healthcare professional may ask you questions such as:
If you think you have alpha-gal syndrome, don't eat red meat until your appointment. If you have a serious reaction, get emergency help.
