Penicillin De-Labeling Clinic

Testing for Penicillin Allergy

Many more patients believe that they are allergic to penicillin than actually are. 

About 10 percent of patients are labeled in their medical record as being allergic. Tests determine that as many as 90 percent of them are not. Testing for an allergy and correcting the patient's chart if found not to be allergic has a number of benefits.

When patients report an allergy, their health care provider commonly prescribes an alternative non-penicillin antibiotic. These medications tend to be more expensive and may come with a higher risk of side effects. They also contribute to increased rates of antibiotic-resistant infections.

In most people, being tagged as penicillin allergic is due to mistaking a reaction such as headache or stomach ache for an allergy. Sometimes the medication is blamed for a patient’s unrelated, measles-like viral rash. In other cases, a person may truly have been allergic to penicillin in the past, but the allergy has gone away over time.

Symptoms of a true allergic reaction can range from a mild skin rash to a severe skin rash or potentially life-threatening anaphylaxis. However, anaphylaxis caused by true penicillin allergy is extremely rare.

How Penicillin Testing Works

Our expert allergists can evaluate a patient’s tolerance of penicillin and other drugs with skin testing in the office. If this test is negative, the patient will take oral doses of the medication under supervision, usually in one or two doses.

These tests have found that most patients who have been labeled allergic to penicillin are not, and are able to take the common antibiotic. 

Many studies have proved the value of penicillin allergy evaluation because health care providers are able to prescribe their patient a less expensive, potentially more appropriate, and more easily tolerated antibiotic. 

Learn about treatment at Lifespan for other pediatric asthma and allergy conditions