When someone has an allergic reaction to a medication, doctors often assume that the person is reacting to the active ingredient itself. Increasingly, though, people are allergic to another ingredient hidden in pills, a sugar from mammals. Do you have such an allergy?
Q. Twenty years ago, I learned I was allergic to beef. I found out a week ago it’s not just beef. I have alpha-gal allergy.
I’m on a mission to find out where mammalian products are hidden. Example: the stearate part of magnesium stearate. Do you happen to know of a list of medications or supplements that contain mammalian products?
Where Is the Sugar from Mammals Hiding?
A. Alpha-gal allergy is a delayed allergic response to a complex sugar from mammals that is not found in humans. The allergic reaction often does not start for several hours after eating meat. Symptoms range from hives or runny nose to stomach cramps, diarrhea, asthma or anaphylaxis.
Blame the Lone Star Tick:
Though it may seem as though this allergy appears out of nowhere, it’s actually induced by the bite of a lone star tick (Amblyomma americanum). People like you with alpha-gal allergy must avoid any sugar from mammals. In practice, this means avoiding all mammalian meat, including beef, pork, lamb, venison, rabbit, bison, goat, etc. Some people must also avoid milk and dairy products. Fish and poultry do not contain the sugar and do not trigger this type of allergic reaction.
Medicines with Mammalian Ingredients:
Since you have this condition, you’ll need to avoid gelatin capsules, protein powders that contain whey, magnesium stearate derived from animals, the cancer drug cetuximab and Creon pancreatic enzymes (Kar et al, Pharmacy Times, May 27, 2015). Desiccated thyroid (Armour, Naturethroid, Westhroid) is also derived from animals and could cause a bad reaction.
We suggest you ask your pharmacist to help you find out whether your medicines contain ingredients derived from mammals. Unfortunately, we do not know of a master list that would make such a task easier.
Learn More about Alpha-Gal Allergy:
We have discussed alpha-gal allergy on our radio broadcasts and podcasts with physicians expert in this topic. You’ll find more information in Show 830: Alpha-Gal Allergy and Show 1003: From Lyme to Alpha-Gal: The Latest on Tick-Borne Diseases.