page contents

Are you allergic to beef and pork?  You may be allergic to gelatin too.

It was just a cheese burger, but Mary awoke 4 hours later, with severe itching.  She went to the bathroom, and took a shower, but within minutes she was dizzy, and threw up.  She ended up on the bathroom floor unconscious.  Her husband called an ambulance, and she had several doses of epinephrine (adrenaline) and steroids before she improved.  Allergic reactions to beef and pork were described over 20 years ago in Australia.  They thought the allergy was related to tick bites from ticks on bandicoots (they look like a mouse).  In Bentonville, Arkansas, a patient died from an immediate reaction to a cancer medication, made from an antibody made from a mammal.  Dr. Tina Hatley Merritt in Arkansas and Dr. Thomas Platts-Mills in Virginia developed a test to evaluate these allergic reactions.  Researchers at Imclone determined the reaction to the cancer medication was from an allergy to a sugar-protein called galactose-alpha-1,3-galactose, abbreviated Alpha-gal.  A landmark article was published in the New England Journal of Medicine, describing this new type of allergic reaction to a sugar plus protein.

A short time later, Dr. Platts-Mills was bitten by several baby seed ticks in Virginia, and had an increase in his IgE (allergy antibody) to Alpha-gal and developed an allergy to beef, pork, and lamb.  Dr. Barrett Lewis in Missouri also noticed an increase in beef and pork allergy in his area.  Then Dr. Platts-Mills and Dr. Scott Commins at the University of Virginia published an article about red meat allergy related to Alpha-gal, and how this can be caused by tick bites, and mostly occur in the mid-south.  The symptoms range from hives and diarrhea to life-threatening allergic reactions with breathing problems and a drop in blood pressure.  The other unique finding is that these reactions can be delayed, up to 6 hours after eating red meat.

People who have allergic symptoms to red meat, may also be allergic to milk and gelatin.  Gelatin that is derived from mammal products can cause similar allergic symptoms.  The symptoms include rashes if gelatin is in a soap or lotion.  If in a medication capsule, can cause stomach aches and even severe allergic reaction.  Gelatin is in several vaccines, and could cause immediate reactions (See Children’s Hospital of Philadelphia Educational Material).  Glycerin may also be derived from lard, but may be from plant sources as well.

All mammals except humans and apes have Alpha-gal.  (Humans do express Alpha-gal in the trophoblast phase of development).  Exposure to pets and farm animals may increase allergy to Alpha-gal.  In a study in Arkansas, all of the patients with allergy to Alpha-gal had previous tick bites, and most of them had exposure to pets.  There is a test available to measure IgE to Alpha-gal.  It is performed by ViroCor-IBT laboratory in Lee Summit, Missouri.  An allergist can also do skin testing for beef, pork, and milk.  The treatment is strict avoidance, but it appears that after 3-4 years of avoidance, the allergy decreases.

Tina Hatley Merritt, MD

The Allergy & Asthma Clinic of Northwest Arkansas

Email: [email protected]
Updated 8/25/2012

Alpha-gal allergy (Mammal glycoprotein)



Beef stock or broth



Brown gravy (made from beef broth)

Gelatin-when made from byproducts of the meat and leather industry

Certain vaccines (See Children’s Hospital of Philadelphia educational material)

Gummy candies

Some ice cream and yogurt

Gelatin dessert


Altoids brand mints

Gelatin capsules

Medications that contain pre-gelatinized starch



Lard (some refried beans contain lard)


Venison (deer)

Avoid contact in a few extreme cases:

Lanolin (sheep)

Sometimes leather (shoes, couches)

Contact with pets/animals-inhaled can trigger cough


Chicken, turkey and fish are not mammals, and do not contain Alpha-gal.