Millions of people wrongly think they are allergic to penicillin thanks to incorrect medical records

People may believe they are allergic to penicillin for a variety of reasons. Credit: PA

Are you allergic to penicillin? If so, are you really sure? It might just be unpleasant side effects


Millions of people mistakenly think they are allergic to penicillin, experts have suggested.

The Royal Pharmaceutical Society (RPS) said patients should check their medical record the next time they visit their GP as up to 95% of people are wrongly labelled as allergic.

The professional body, which represents pharmacists and pharmacy students, said those who are not able to take penicillin could lead to people being put on other antibiotics which may be less effective.

This means they could take longer to recover and may need to go to hospital in some cases.

A paper published in the British Journal of Clinical Pharmacology in 2019 suggested six to 10% of the general population in the UK and US are recorded as allergic to penicillin.

But “emergent research shows that 90–95% of these labels are found to be incorrect following comprehensive allergy testing” the RPS says.

Other research published in the Journal of Antimicrobial Chemotherapy in 2019 estimated that incorrect penicillin allergy records affect 2.7 million people in England alone.

Why do people wrongly think they are allergic?

According to the RPS, people may believe they are allergic to penicillin for a variety of reasons, such as if suffering common side-effects of the drug such as nausea or diarrhoea.

Sometimes, the infection being treated may also cause issues such as a rash which is regarded as an allergic reaction and reported as such, it said.

In addition, an allergy reported many years ago, perhaps in childhood, may have settled down but the perception of having an allergy remains.

Compared with patients without a penicillin allergy record, those who have one have an increased risk of death, published data has suggested.

A petri dish that holds a sample of mould that enabled Alexander Fleming to discover the antibiotic power of penicillin. Credit: PA

What should I do if I'm labelled as allergic to penicillin?

Patients have been advised to talk to their pharmacist or other health professional to help understand whether they are allergic or if it is actually just a side effect.

RPS spokeswoman Tase Oputu said: “Every medicine has benefits and harms and I urge patients to ask questions about a penicillin allergy label on their medical record.

"Many individuals are at low or very low risk of having a genuine penicillin allergy and we often find that after careful investigation that they can take penicillin safely.

“Others, who may have had a severe reaction in the past, will need allergy testing and in some cases may never be able to take penicillin.“

Allergic reaction vs side-effect symptoms

Mild to moderate allergic reactions include:

  • a raised, itchy skin rash (urticaria, or hives)

  • coughing

  • wheezing

  • tightness of the throat, which can cause breathing difficulties

Side-effects of antibiotics can include:

  • nausea

  • bloating and indigestion

  • diarrhoea


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