# Bullous Pemphigoid Secondary to Dipeptidyl Peptidase-4 (DPP4) Inhibitor: A Case Report

## TL;DR

An 80-year-old diabetic man developed bullous pemphigoid, a skin condition, possibly linked to a diabetes medication called DPP4 inhibitor.

## Contribution

This case report highlights a potential cause-and-effect relationship between DPP4 inhibitors and bullous pemphigoid.

## Key findings

- A diabetic patient developed bullous pemphigoid symptoms while using a DPP4 inhibitor.
- Symptoms improved with topical corticosteroids, suggesting a drug-induced autoimmune response.
- The case supports a possible link between DPP4 inhibitors and bullous pemphigoid.

## Abstract

Bullous pemphigoid (BP) is a rare acquired subepidermal autoimmune disease characterized by the presence of blisters on the skin. Recently, a possible association has been reported between the use of DPP-4 inhibitors, an oral antidiabetic, and an increased risk of BP. The mechanisms underlying this increased risk remain poorly understood. We present the case of an 80-year-old diabetic man who developed scattered blistering pruritic lesions on the trunk and limbs, which had been progressively worsening over approximately 6 months and difficult to resolve. After investigating his medical history and observing significant improvement following the administration of topical corticosteroids, the clinical presentation was associated with the use of a DPP-4 inhibitor. In conclusion, the case presented suggests a cause-and-effect relationship between BP and DPP-4 inhibitors. Early recognition of these adverse reactions is crucial to establish appropriate interventions to prevent the progression of conditions such as BP.