Allergic to penicillin? Might want to check.

DALLAS – January 2017 – If your health records indicate that you are allergic to penicillin, consider verifying that with an allergy test.

A recent study by UT Southwestern researchers found that 90 percent of individuals whose health records indicated a penicillin allergy did not show a reaction to the antibiotic in an allergy test.

Reasons may vary: People outgrow allergies; a rash caused by a viral infection can be mistaken as a reaction to the antibiotic; and, often, reported penicillin allergies are based on hazy, incorrect recollections.

“Penicillins are some of the safest and cheapest antibiotics available and people who are reported to be allergic often get antibiotics that are costlier and potentially more toxic,” says Dr. Min Lee, a pediatric allergist at UT Southwestern Medical Center.

People who believe they are allergic to penicillin take a broad-spectrum antibiotic rather than penicillin, which can knock out beneficial bacteria that live in our guts and on our skin, setting the stage for harmful bacteria that are tough to treat.

“People who have a reported penicillin allergy are more likely to be hospitalized for C. difficile and MRSA, bacteria that are resistant to multiple antibiotics and can cause life-threatening infections,” says Dr. Lee, who practices at Children’s Health in Dallas.

Fortunately, penicillin allergy can be easily checked by an allergist. It’s a two-step process: first a skin test and, then if that’s negative, an oral penicillin challenge.

 Dr. Lee says a good time for penicillin-allergy testing to take place is before a child transitions from pediatric care to adult medical care. “Even if a child was allergic 10, 15 years ago, they may not be now and if not, it’s a good time to get the label removed from health records.”

Dr. Lee is Assistant Professor of Pediatrics and Internal Medicine at UT Southwestern who practices at Children’s Health.

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