Drug-Induced Bullous Pemphigoid: Emerging Evidence with Vildagliptin and Teneligliptin Use in a Tertiary Care Hospital – A Case Series

Background: Bullous pemphigoid (BP) is an autoimmune subepidermal blistering disorder of the elderly. Dipeptidylpeptidase-4 (DPP-4) inhibitors (“gliptins”) have been increasingly recognized as potential drug-induced triggers.

Objective: To describe eight cases of gliptin-associated drug-induced Bullous Pemphigoid and to highlight the emerging evidence implicating vildagliptin and teneligliptin use in Indian patients.

Methods: Eight patients with type 2 diabetes mellitus who developed BP during gliptin therapy were evaluated at a tertiary-care teaching hospital. Diagnosis was confirmed by clinical findings, histopathology, and direct immunofluorescence (DIF). All cases were reported to the Adverse Drug Reaction Monitoring Centre (AMC) under the Pharmacovigilance Programme of India (PvPI), R.G. Kar Medical College and Hospital, prior to causality assessment using the WHO–UMC and Naranjo scales.

Results: Six patients had received vildagliptin and two teneligliptin. Mean age was 63 years (range 52–74); female:male = 4:4. Latency period 2–8 weeks. All developed pruritic erythematous plaques and tense bullae over trunk and limbs, with mucosa spared. Histopathology revealed subepidermal blisters with eosinophilic infiltrates, and DIF showed linear IgG and C3 deposition along the basement membrane. Drug withdrawal led to remission within 1–3 weeks. No relapse occurred over three months. All cases were rated “probable” by causality assessment.

Conclusion: Vildagliptin and teneligliptin can precipitate drug-induced Bullous Pemphigoid in elderly diabetic patients. Early recognition, pharmacovigilance reporting, and drug withdrawal are crucial. Teneligliptin may represent an emerging pharmacovigilance signal.