Delabeling of penicillin allergy

Many people worldwide carry a “penicillin allergy” label. However, in more than 90% of cases, this label can be removed after thorough assessment with an anamnesis and a provocation test or trial treatment with penicillins.

An incorrect label can lead to several complications when a patient has an infection that needs to be treated.

For example, alternative antibiotics more often cause side effects, postoperative wound infections occur more frequently, and the cost of alternative antibiotics is higher. In addition, infections are more difficult to treat and more often result in longer hospital stays.

Within JYZ, a flowchart was developed to categorise patients into three categories based on a questionnaire.

Very low risk of penicillin allergy

Patients who experienced a side effect after taking the antibiotic in the past, or patients who indicate that a family member is allergic to penicillin but who themselves have not developed a reaction. These are patients with an incorrect label, which can be removed immediately. No further investigation is required.

Low risk of penicillin allergy

Patients who no longer remember the reaction, those who had a maculopapular rash more than 10 years ago, or who developed isolated itching.

In these patients, the treating physician may choose to perform a tolerance test (1 g amoxicillin PO). If the treating physician cannot or does not wish to do this, the patient can be referred to an allergist. The allergist can then schedule a tolerance test, possibly delabel after further questioning, or opt for a more extensive work-up with intradermal testing.

Intermediate or high risk of penicillin allergy

Patients with a real risk of penicillin allergy may have experienced an allergic rash, swelling of the throat/tongue/face/lips, breathing difficulties, a drop in blood pressure, shock, etc. In patients with an intermediate or high risk, it is important to refer them to an allergist for further evaluation.