A Review on: - Losartan in Hypertension and Heart Failure: Pharmacovigilance and Adverse Drug Monitoring

Abstract

Losartan, the first angiotensin II receptor blocker (ARB) introduced for clinical use, has become a cornerstone therapy for hypertension, heart failure, and diabetic nephropathy. Its mechanism of action—selective blockade of angiotensin II type 1 (AT1) receptors—offers hemodynamic and renal protection with fewer side effects compared to angiotensin-converting enzyme inhibitors (ACEIs). Despite its favorable efficacy profile, Losartan is associated with adverse drug reactions (ADRs) ranging from mild dizziness and fatigue to rare but life-threatening events such as hyperkalemia, renal dysfunction, and angioedema. Given the widespread and long-term use of ARBs in diverse populations, pharmacovigilance plays a pivotal role in identifying, monitoring, and preventing ADRs. This review consolidates evidence from clinical trials, case studies, and pharmacovigilance databases, highlighting the safety concerns of Losartan, the need for ADR monitoring, and the responsibilities of healthcare professionals and patients in ensuring rational drug use.

Keywords

Introduction

Hypertension and heart failure remain two of the most prevalent cardiovascular disorders worldwide, contributing significantly to morbidity and mortality. Pharmacological management often requires long-term therapy, making drug safety monitoring an essential part of treatment. Losartan, an angiotensin II receptor blocker (ARB), was approved in 1995 as the first agent of its class. Unlike ACE inhibitors that inhibit the conversion of angiotensin I to angiotensin II, Losartan selectively blocks AT1 receptors, thereby preventing vasoconstriction, aldosterone release, and sodium retention. This mechanism leads to reduced systemic vascular resistance, improved cardiac workload, and renal protection. The World Health Organization (WHO) and several guidelines (e.g., ACC/AHA, ESC) recommend ARBs, including Losartan, as first-line therapy for hypertension and heart failure, particularly in patients intolerant to ACE inhibitors. However, prolonged use demands vigilance regarding ADRs, especially in elderly patients and those on multiple medications. This review emphasizes Losartan’s pharmacological aspects, therapeutic applications, reported ADRs, and the importance of pharmacovigilance in ensuring safe usage.

Distribution: Highly protein-bound (~99%).

1. Essential Hypertension – Reduces blood pressure effectively as monotherapy or in combination with diuretics.

• Identification of new ADRs not seen in clinical trials.
• Recognition of changes in ADR frequency or severity.
• Updating risk-benefit profiles in real-world use.
• Guiding physicians and pharmacists in safe prescribing.
• Reporting Systems
• India: Pharmacovigilance Programme of India (PvPI).
• USA: FDA MedWatch.
• UK: Yellow Card Scheme.
• Global: WHO-Uppsala Monitoring Centre (VigiBase).
• Encouraging ADR reporting by healthcare professionals and patients ensures safer use of Losartan.

MATERIALS AND METHODS

This narrative review is based on secondary research. Data were collected from:

• Peer-reviewed journals (PubMed, ScienceDirect, Springer).
• Pharmacovigilance databases (WHO-VigiBase, CDSCO-PvPI)
• Case reports and regulatory guidelines.

Search terms included: “Losartan,” “Adverse Drug Reactions,” “Pharmacovigilance,” “ARB safety,” “Hypertension,” and “Heart Failure.” Literature between 2010–2025 was reviewed.

CONCLUSION

Losartan remains one of the most effective and widely prescribed ARBs, offering significant benefits in hypertension, heart failure, and diabetic nephropathy. However, like all drugs, it carries risks of ADRs ranging from mild symptoms to life-threatening complications. Pharmacovigilance plays a crucial role in ensuring its safe use by monitoring, identifying, and preventing ADRs. Strengthening awareness, reporting systems, and collaboration between healthcare providers and patients can enhance therapeutic outcomes while minimizing risks.

ACKNOWLEDGEMENTS

The authors gratefully acknowledge the guidance of faculty members of the Department of Pharmacy, Jagdamba Education Society’s S.N.D. College of Pharmacy, Nashik, Maharashtra, for their academic support and access to scientific databases.

• Authorship Statement

All authors contributed equally to the conception, drafting, and approval of this manuscript.

• Conflict of Interest

The authors declare no conflicts of interest related to this work.                                          

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