Majority of people not allergic to intravenous penicillins, say ACAAI allergists

Most people who think they’re allergic to penicillin have been told so by a doctor after they’ve had a reaction to the drug. And the majority, even though they’ve never been allergy tested, never take penicillin again.

A study presented at the American College of Allergy, Asthma and Immunology (ACAAI) Annual Scientific Meeting, examined the records of 15 patients who, after being told they were penicillin-allergic, tested negative for penicillin allergy, and were then able to be treated with intravenous penicillin on multiple occasions.

“We found intravenous penicillins to be safe for repeated use in patients who had been told they were allergic,” said allergist David Khan, MD, study author and ACAAI fellow. “Of the patients whose records we examined, there were no adverse drug reactions or evidence of recurrence of their penicillin allergy. There is often thought to be a higher risk in patients who get intravenous penicillin, but we did not find this to be the case. Previous reported reactions included rash, hives and swollen lips, but none of those reactions occurred after allergy testing, and treatment with multiple courses of intravenous penicillins.”

About 10 percent of Americans carry a label of penicillin allergy, and others have an “allergic history” to other antibiotics. As a result, they are often prescribed more toxic, dangerous and expensive antibiotics that might not be necessary.

“Recent research has shown that patients who are labeled penicillin-allergic and take other antibiotics are more likely to have poor outcomes, such as development of colitis, longer hospital stays and greater numbers of antibiotic-resistant infections,” said allergist Roland Solensky, MD, ACAAI member and meeting presenter. “There has been a push to be more proactive and evaluate patients with history of penicillin allergy even when they’re well and not in need of an antibiotic. The vast majority turn out not to be allergic and can be treated with penicillin.”

At the Annual Meeting, Dr. Solensky will present “Drug allergy: options beyond avoidance” where he will discuss options for patients who have drug allergies, as well as patients who have been told they have drug allergies, but do not.

“Anyone who has been told they are penicillin allergic, but who hasn’t been tested by an allergist, should be tested,” said Dr. Khan. “An allergist will work with you to find out if you’re truly allergic to penicillin, and to determine what your options are for treatment if you are. If you’re not, you’ll be able to use medications that are safer, often more effective and less expensive.”