What Is Alpha-gal Syndrome?

Understanding Alpha-gal Syndrome: A Guide to Symptoms, Treatment, and Prevention

By George Garber, RN
Infection Control Preventionist

 

Alpha-gal syndrome (AGS) is a serious, potentially life-threatening allergic condition that can occur after a tick bite. It is named after a molecule called alpha-galactose. This reaction typically begins with a bite from a tick (or possibly a chigger). Symptoms of Alpha-gal Syndrome usually do not occur until three to six hours after consuming red meat or other products, such as beef, pork, or venison. While symptoms can arise at any time of day, many patients are often awakened from sleep due to symptoms triggered by the meat they consumed hours earlier.

In the U.S., the lone star tick is the primary source of alpha-gal allergy. This tick is concentrated in the eastern and south-central regions of the U.S. and is commonly carried by deer. In Europe, Australia, and Asia, the alpha-gal molecule has been found in various types of ticks.

Symptoms occur after individuals eat red meat or are exposed to other products made from mammals. Because of this, AGS is also known as red meat allergy or tick bite meat allergy. While the lone star tick is the species most commonly associated with AGS, other types of ticks may also be involved. A CDC report indicated that between 2010 and 2022, more than 110,000 suspected cases of AGS were identified. Most reported cases in the United States occur in the Southern, Eastern, and Central states—areas where lone star ticks are prevalent. In other countries, different tick species have also been linked to AGS.

 

Symptoms of an alpha-gal syndrome reaction often include:

• Rashes
• Hives
• Nausea
• Vomiting
• Difficulty breathing
• Low blood pressure
• Dizziness
• Stomach pain
• Extreme itching

 

Treatment

Alpha-gal syndrome does not go away, but symptoms can be managed by avoiding:

• Meats, organs, and blood from mammals
• Dairy products
• Gelatin and other animal derivatives
• Food cooked with lard
• Any food containing mammalian products
• Drugs, medicines, hygiene products, and household items with animal by-products
• Anything containing the thickening agent carrageenan
• The cancer medication cetuximab

 

While AGS can affect individuals of all ages, most reported cases have been observed in adults.

Although AGS is associated with tick bites, further research is needed to understand the role ticks play in initiating this condition and why certain individuals develop AGS.

Prevention

Preventing tick bites is crucial and may reduce your chances of developing AGS or other illnesses.

Before you go outdoors:

• Avoid grassy, brushy, and wooded areas where ticks may be present.
• Walk in the center of trails.
• Treat clothing and gear with permethrin, or purchase pre-treated items.
• Use Environmental Protection Agency (EPA)-registered insect repellent.

 

After you come indoors:

• Check your clothing for ticks.
• Examine your gear and pets for ticks.
• Shower and perform a thorough tick check.
• If you find an attached tick, remove it immediately.
• Learn how to prevent ticks on your pets and in your yard.