Telmisartan Adverse Drug Reactions: A Clinical Pharmacist’s Review with Case Insight

Telmisartan is a long-acting angiotensin II receptor blocker widely used for hypertension management. Although generally well tolerated, it has been associated with various adverse drug reactions (ADRs) ranging from mild symptoms to serious events. To review telmisartan’s ADR profile from a clinical pharmacist’s perspective and illustrate key insights through a case of drug-induced acute kidney injury (AKI). A comprehensive literature review and analysis of the Pharmacovigilance Programme of India data were conducted. A 40-year-old male who developed pre-renal AKI following dose escalation of telmisartan is presented. Common ADRs include dizziness, headache, diarrhoea, and respiratory symptoms. Serious reactions encompass hyperkalemia, angioedema, hypotension, and AKI. PvPI reports have highlighted rare cutaneous reactions such as lichenoid keratosis. In the case study, serum creatinine rise from 1.3 to 1.8 mg/dL within 48 hours of increasing the telmisartan dose and normalized after discontinuation. Vigilant monitoring and pharmacist-led interventions are essential to detect and manage telmisartan-related ADRs, optimize therapy, and ensure patient safety.