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Penicillin: You might not be allergic after all

May 28, 2022—Think you're allergic to penicillin? Maybe you were diagnosed in childhood. But it might not be correct today. In fact, according to the National Institutes of Health, while 10% of Americans have a penicillin allergy in their medical records, only 1% of Americans are actually allergic.

There are a few reasons for this. Many folks are diagnosed with a penicillin allergy in childhood, often because of a rash. But that rash might not be caused by an allergy. It may have been caused by a virus. Others may have simply assumed they're allergic because a parent was.

One recent study published in JAMA Network Open found that about 8% of children with a penicillin allergy in their medical records had never been prescribed the medicine. And when children whose records say they are allergic to penicillin get allergy testing, 95% of them turn out to not have an allergic response.

Even a true penicillin allergy may not be lifelong. In fact, according to the NIH and other experts, 8 in 10 people with a confirmed allergy to penicillin are no longer allergic to it 10 years later.

Why does it matter?

There's a huge cost to avoiding penicillin. It's one of the cheapest, safest, most effective antibiotics for many infections. People who avoid it may have to be treated with pricier, more powerful antibiotics with more side effects.

Using these more powerful antibiotics may also fuel antibiotic resistance. That's what happens when bacteria evolve into "superbugs" that become harder and harder to kill.

Clearing up the confusion

Studies published in Open Forum Infectious Diseases suggest two fairly easy ways to help identify people who mistakenly believe they're allergic to penicillin.

The first is a short survey that healthcare providers can give to patients. In one study, the questions alone were able to rule out an allergy in 20% of people who thought they were allergic to penicillin.

The next step, if needed, is a penicillin allergy skin test (PAST). The skin is pricked with a small amount of penicillin to see if any skin irritation develops. If not, the person can be given penicillin drugs in a doctor's office and watched for a reaction. This kind of testing can rule out an allergy in many people.

There's a clear takeaway here. If you think you're allergic to penicillin, talk to your doctor. Your medical history or a PAST may reveal otherwise. And that can open up new options for your healthcare.

How much do you know about antibiotics?

Used the right way, antibiotics can help you bounce back from an infection. But used the wrong way, they can be harmful. Test your know-how with this quiz.

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