Do you have a penicillin allergy?

Penicillin can be a very useful drug, it can be used to treat respiratory tract infections, scarlet fever, and various infections which include the ear, skin, mouth, and throat.  However there is one theoretical one set back.  In the United States, one in every ten Americans are allergic to penicillin.  Or at least they could theoretically be allergic to the drug.  If someone were to have a penicillin allergy, symptoms could include skin rash, hives, itching, fever, swelling, shortness of breath, wheezing, runny nose, watery and itchy eyes, and anaphylaxis. Most people, however,  who think they are allergic to the drug, actually are not.

Allergists and specialists around the country “are calling for more testing of whether patients are really allergic, because research finds that most who’ve been told in the past that they are allergic to penicillin are actually not.” (WBUR)  According to Dr. David Lang, Chairman of the Allergy and Clinical Immunology Department at the Cleveland Clinic, says that, “If you consider yourself to be allergic to penicillin, you shouldn’t be complacent, you should discuss this with your physician.”   Dr. Katherine Atkinson at Atkinson Family Practice is concerned, “We need to be able to treat infections! If a patient thinks they are allergic to the medicine we want to use to treat them, then we have our hands tied! We need the knowledge so patients can be treated, especially for serious infections.”

Dr. Erica Shenoy, an Infectious Disease Specialist for Massachusetts General Hospital in Boston, states that “They’re very good drugs to treat a whole host of infections and also to prevent infections, for example to prevent infections in patients who are undergoing surgery.”  Dr. Kimberly Blumenthal, who is an Allergist for Massachusetts General Hospital says the term “allergy” is applied to penicillin reactions far too broadly when it comes to diagnosing the allergy to the drug. 

“So you might have had a headache, or nausea, or fatigue, and that ends up in what we call the allergy section of your health record,” Blumenthal says, even though those symptoms reflect an intolerance, not an allergy. (WBUR)

According to the Mayo Clinic, a misdiagnosed penicillin allergy can result to using less effective medications, and could cost more money.  So to be certain that a penicillin allergy is not the case, it is recommended that someone who thinks they have a penicillin allergy, should get tested.  But what does an allergy test entail?  Well, there are two different tests, a “skin test” and a “graded challenge.”

A skin test is usually the first test that gets administered, the test entails an allergist administering a small amount of penicillin to the skin.  If the reaction is positive, it will cause a red, itchy, raised bump to appear on your skin.  This is a pretty simple test, however it’s a little more difficult to determine whether or not you really have a penicillin allergy.  “A negative test result usually means you’re not allergic to penicillin, but a negative result is more difficult to interpret because some kinds of drug reactions cannot be detected by skin tests.” (Mayo Clinic)

So if the skin test doesn’t work out, then the allergist will go to the next level of diagnosis called the “graded challenge.”  If a graded challenge is required, you will be given up to five doses of penicillin.  First dose being small then gradually going up as needed to determine whether or not you have an allergy.  If there are no allergic reactions to the drug, then you are deemed not allergic to penicillin.  But if you are allergic to only one type of penicillin, then your provider may recommend a graded challenge with a different type of penicillin. In hopes that the alternate drug would be less likely to cause an allergic reaction.

If you feel you have a penicillin allergy, but are unsure, contact one of our providers and they will refer you to one of our outside allergists in the local area.  You can contact the office at (413) 549- 8400 to schedule an appointment or talk to one of our providers or staff directly over the phone.

Goldberg, Carey. “Think You’re Allergic To Penicillin? Maybe not Specialist Say, And That’s Worth Knowing.” WBUR, Boston University, 18 Jan. 2019.

Mayo Clinic Staff. “Penicillin Allergy.” Mayo Clinic, Mayo Foundation for Medical Education and Research.