I recently saw a woman who had an anaphylactic reaction after receiving the flu shot for the 1st time. It is exceptionally rare to have anaphylaxis (the most severe allergic reaction) after a flu shot. This woman’s case will bring out an important point that may save others.
This patient didn’t have a history of egg allergy, which is the focus of most doctor’s questions before getting the flu shot. In her case, there was no history of egg allergy, and in fact, she ate eggs that same morning with no reaction.
She could have been allergic to the vaccine itself, which is possible, and I recently had a patient that I skin tested with the flu vaccine who showed a positive test. Many times, patients can be allergic to the preservatives in the flu vaccine: such as thimerosol or formaldehyde.
This can be avoided by using the preservative free, single dose flu vaccine. The interesting piece of history in my patient with the severe allergic reaction was when she mentioned she was allergic to band-aids; and, she added matter-of-factly that she was latex allergic. Ahh! This was important. The patient showed me the package insert from the vaccine she was given. It was from a multi-dose vial, which means the injection had to be drawn up through a rubber stopper. It is most likely she received small particles of latex-rubber in the injection and this is what precipitated her anaphylactic reaction to the flu shot.
My recommendation for doctors is: ask and check to make sure your patient isn’t latex allergic; if they are use a single dose vial. My advice to all patients: if you have latex-rubber allergy be sure to ask your doctor for a single-dose vial.
Dean Mitchell, MD
