Evidence Hub

Cross Reactivity of Acute Generalized Exanthematous Pustulosis Among Proton Pump Inhibitors: Case Report

W. Widyati, Eko Riyanto, Yudadi Redemptus

Open Dermatology Journal, 2026

Abstract

Introduction Acute generalized exanthematous pustulosis (AGEP) is an acute pustular eruption characterized by widespread nonfollicular sterile pustules. AGEP is a rare adverse drug reaction with an incidence of 1 to 5 cases per million per year. This condition was accidentally discovered in a patient treated with two different proton pump inhibitors (PPIs) consecutively. Case Presentation A 47-year-old male developed pustulosis within a couple of hours after being injected with pantoprazole 40 mg. After 3 days of stopping pantoprazole, the patient was injected with lansoprazole 30 mg, and pustulosis redeveloped. Discussion Several studies have reported that pantoprazole can induce AGEP in sensitive patients, but the incidence is rare. In the current case, two different PPI drugs induced the condition in the same patient. This showed cross-reactivity between pantoprazole and lansoprazole in inducing AGEP. The current study is the first case report on cross-reactivity of PPIs in AGEP. According to previous results, cross-reactivity in PPIs is largely due to a similar chemical structure. Omeprazole, esomeprazole, and pantoprazole have changed their benzimidazole rings, while lansoprazole and rabeprazole have modified their pyridine rings. Therefore, cross-reactivity is often observed within the same group of benzimidazoles or pyridines. In the current case, the cross-reactivity cannot be explained by those patterns. A safe alternative PPI can be identified by a skin test, which…

How strong is the evidence?

Evidence Hub reads this as a case report, done in people. Its evidence level is 5 of 5 (Very low · case / narrative / animal / in vitro / in silico). Case reports, narrative reviews, and animal, cell or computer-model studies give the weakest evidence for human health.

How the five levels of evidence work. The level is assigned automatically from the abstract and can be wrong, so check the paper.

Read the paper

Related studies

Go deeper in Evidence Hub

Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.

Open this study Sign up free