Cornish pharmacist leads research to address problem of incorrect penicillin allergy labelling

A clinical pharmacist from Cornwall has been funded by the National Institute for Health and Care Research (NIHR) to investigate the best way to treat patients incorrectly labelled as allergic to penicillin.

Neil Powell successfully applied for an NIHR Clinical Doctoral Research Fellowship to develop and deliver his study, Removing Erroneous Penicillin Allergy Labels (REPeAL).

Neil, a Consultant Antimicrobial Pharmacist at Royal Cornwall Hospitals NHS Trust, will investigate the best way to decide if patients can receive penicillin, and how to integrate this decision-making process into routine clinical practice.

Research has shown that patients with a penicillin allergy record do less well than patients without. As a group, these patients are given more antibiotics, and often receive less effective alternatives to penicillin.

Around one in ten people have a penicillin allergy in their medical notes, but previous studies suggest 9 out of 10 such patients are able to safely take the drug. Possible reasons for being mis-labelled as allergic to penicillin include: experiencing a mild side effect – an intolerance - and not a true allergy; having grown out of an allergy; or attributing a reaction to penicillin when it was not the cause. 

This means a large number of patients are unnecessarily denied penicillin and put at risk of poorer outcomes.

Identifying all of the 90% of patients who could be safely ‘delabelled’ would require skin testing and allergy expertise, which not all hospitals have. For patients with a history of mild intolerance or some low-risk potential allergy symptoms such as mild rashes, ward doctors, nurses and pharmacists have the skills needed to assess whether it is safe to give penicillin, although this is not routine practice. 

REPeAL aims to change this by developing and implementing a structured set of questions and a decision support aid, to help clinicians decide whether or not to offer penicillin to those with an allergy recorded.

Neil said: “Penicillin is generally well tolerated, it’s effective, safe, and therefore we want to be using it. In this study we are looking to identify the people who aren’t likely to have an allergic reaction and can be safely delabelled.

“There are lots of other reasons for conducting this study, for example if you've got someone with a resistant bug and a penicillin allergy, their antibiotic options are limited. Also, a lot of the new antibiotics are based on penicillin.

“But the main reason is to optimise the use of penicillin and ensure as many people as possible are able to take it while in hospital.”

He continued: “About half of patients who have a penicillin allergy on their records will give a low-risk history, reporting they had nausea or vomiting as a result of taking penicillin, or it gave them a headache, or they had a skin reaction but it was mild.

“We can remove many of these allergy records straightaway, as what they are describing is not an allergy, and if we explain we want to use penicillin, patients invariably say that’s fine. In some cases we can also give patients an oral dose of penicillin to prove to them that they are not allergic.

“Any higher risk patients, for example those that have a history of anaphylaxis, we're not including for now. But the aim is that we will be able to in future.”

As part of the study, Neil is reviewing the medical literature to learn how hospitals in other countries have tried to remove incorrect penicillin allergy records. He will look at the effect of this on the amount of penicillin and second choice antibiotics hospitals used, patients’ infection outcomes and any side effects.

Neil is also bringing in behavioural science experts to guide him in discussing patients’ concerns about being delabelled, to ensure the process is acceptable to them and appropriate information and reassurance is available.

He will monitor patients for any harm as a consequence of being delabelled, and the rates of side effects.

REPeAL is currently running at RCHT, and the Trust has also recently become the UK co-ordinating site for iNAAN, an international study looking at the impact of de-labelling on patient outcomes.

For more information on the NIHR Fellowship programme, visit the website: https://prod.drupal.rdn.nihr.ac.uk/explore-nihr/academy-programmes/fellowship-programme.htm