What is it?

A tick bite can be more than an annoyance. For some people, checking hay for dryness, hand-weeding vegetable crops or taking a hike in the woods is the first step in acquiring a life-changing allergy to meat and any products with mammalian ingredients.

The allergy and all that’s associated with it is alpha-gal syndrome (AGS), dubbed the “red meat allergy.” Sharon Forsyth is a founder of the Alpha-gal Alliance; she has the alpha-gal allergy and is a warrior for a growing group of people who find themselves seriously ill with a variety of allergy symptoms following the bite of a lone star tick.

Forsyth explained that AGS is an unusually severe allergy to a sugar, but “not the kind you put in coffee.”

“It’s a special sugar called galactose-alpha-1,3-galactose,” said Forsyth. “Its nickname is alpha-gal. It’s caused by tick bites, and in the U.S., it’s usually caused by the lone star tick.” However, bites from other tick species can result in AGS.

While the lone star tick was originally concentrated in the South and Southeast, its range is rapidly expanding. It’s now found in New York and New England, as far west as Nebraska, in most of Iowa, Illinois, Indiana, Ohio, Pennsylvania and in the upper Midwest.

Alpha-gal is found in most mammals, including cows, goats, pigs, sheep, deer, cats, dogs and all other non-primates. It’s unclear whether the lone star tick’s saliva or bits of alpha-gal from the tick’s previous blood meals are responsible for the allergic reaction in which the immune system detects alpha-gal as foreign and responds with an allergic reaction.

In addition to being present in meat from mammals, alpha-gal is found in products made from ingredients from mammals including foods, drugs and medical devices, personal care products and household products.

AGS begins with a bite from a lone star tick, but allergy symptoms aren’t immediate. Those who have multiple tick bites may have a faster onset, but Forsyth said it usually takes at least six weeks.

“Then you have an alpha-gal exposure,” said Forsyth. “This would usually be something like eating a burger or a steak, dairy products or a medication that contains alpha-gal. Hours later, you develop a reaction.” The delayed reaction is what makes this allergy difficult for doctors to diagnose.

For most people, allergic reactions to food occur every time the food is eaten, while others only experience alpha-gal symptoms occasionally.

“You might eat a hamburger every day for a month and never have a reaction,” said Forsyth, “then eat a hamburger and have a severe reaction that puts you in the hospital. Just because you don’t react every time doesn’t necessarily mean you have a ‘mild’ version of this allergy.”

Most allergies cause typical symptoms such as hives and swelling. Alpha-gal patients sometimes have these symptoms, but in some cases, people get AGS that mimics IBS or arthritis, with no hives or other allergic symptoms. These characteristics also make AGS difficult to diagnose, and many people have the condition without knowing what it is.

Alpha-gal reactions are often influenced by co-factors such as alcohol, exercise and NSAID drugs that may result in more severe allergic reactions. “Some people with alpha-gal only react when a co-factor is involved,” said Forsyth. “They might be able to eat a hamburger and not react, but having a hamburger with a beer or going for a run afterwards might result in a severe, life-threatening reaction.”

The list of problematic foods is long and includes many common foods and beverages: beef, pork, lamb and venison are off the menu, along with organ meats, which often contain higher levels of alpha-gal than muscle meats. Milk and dairy products are also triggers. Foods made with or that contain gelatin and numerous other mammal-derived ingredients are triggers too.

People with AGS also have allergic reactions to foods and drinks that contain carrageenan, a common food ingredient. “Carrageenan doesn’t come from a mammal,” said Forsyth. “It comes from red algae, and like mammals, also makes alpha-gal.”

As if food allergies aren’t enough, Forsyth said 75% of those with AGS have reacted to a medication, and 50% have had a severe, life-threatening reaction to a medication.

“Some medical products are even more dangerous for us than any food,” she said. “The cancer drug cetuximab has been fatal to some people with AGS.”

For more information on AGS, visit alphagalinformation.org.

Part 2 will include information on alpha-gal symptoms and the mammalian connection.