What Is Alpha-Gal Syndrome?

Medically Reviewed by Poonam Sachdev on October 19, 2021
3 min read

Alpha-gal syndrome is an allergy to things like beef, pork, lamb, venison, rabbit, and other animal products that come from mammals. It was first discovered in 2009. Alpha galactose, the source of the allergy, is a sugar present in most animal cells. Alpha-gal symptoms develop after certain tick bites.

Alpha-gal syndrome is caused when a tick bites you, and that bite gives you the alpha galactose molecule. In the U.S., the lone star tick is the primary source of alpha-gal allergy.

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

Alpha-gal symptoms differ from other allergic reactions in that they are significantly delayed. Reactions to animal products will happen within eight hours of eating. This delay, and the relative newness of alpha-gal's discovery, means the syndrome goes undiagnosed. 

Alpha-gal syndrome reaction symptoms often involve:

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

However, symptoms of alpha-gal vary from case to case. The severity of these symptoms also varies from person to person and can become more severe as time goes on. Drinking alcohol or exercising after you eat may slow down the reaction time. Sometimes the symptoms of a reaction from an alpha-gal allergy can even lead to death. 

Alpha-gal syndrome doesn’t go away, but you can manage symptoms by avoiding:

  • Meats, organs, and blood of mammals
  • Dairy products 
  • Gelatin and other animal derivatives
  • Food cooked with lard 
  • Any food with any sort of mammalian product
  • Drugs, medicines, hygiene products, and household products with animal bi-products 
  • Anything with the thickening agent carrageenan 
  • Flounder eggs
  • The cancer medicine cetuximab

You can take antihistamines or another type of allergy medicine to manage your symptoms if you have a reaction. However, if you are having an extremely severe reaction, you will need to be injected with epinephrine or even go to the emergency room. Many people with alpha-gal even carry around an EpiPen.

Alpha-gal is still a relatively new allergy, so not much is known about it. However, most cases in the U.S. are found in the southeastern and midwestern regions. People who spend more time in nature are more likely to be bitten by a tick. 

If you think you have alpha-gal syndrome, you should see your doctor or go to an allergy specialist. They will get a medical history. If you think you have been exposed to ticks, mention that. 

Your provider will order a physical exam and check for specific antibodies in your blood that could indicate you have alpha-gal. If your doctor is unable to do this test, they may do a test in which they expose a small part of your skin to a tiny amount of alpha-gal to check for a reaction.

Some preliminary evidence suggests that an allergy to red meat from alpha-gal syndrome may go away within five years of being bitten.

The best way to prevent alpha-gal syndrome is to:

  • Avoid long grass, brush, and wooded places where ticks are plentiful.
  • Wear pants and long sleeves when walking in the woods.
  • Put the chemical permethrin on your clothing and gear.
  • Use tick repellents.

Once you come back indoors:

  • Check your clothing for ticks.
  • Shower and do a tick check on your naked body.
  • If you see a tick on your clothing or skin, remove it immediately with tweezers, being careful not to break it.