Adverse drug reactions and pharmacovigilance

Abstract

Adverse Drug Reactions (ADRs) represent a significant challenge to patient safety and public health worldwide. Historical evidence demonstrates that even commonly prescribed and seemingly safe medications, particularly antibiotics and other therapeutic agents, may produce harmful and sometimes fatal reactions. Globally, structured drug safety monitoring evolved following landmark events such as the thalidomide tragedy in 1961, which led to the strengthening of international pharmacovigilance systems under the guidance of the World Health Organization. In India, organized efforts in ADR monitoring began in the late 20th century, with formal participation in the WHO International Drug Monitoring Programme in 1997. Subsequent initiatives, including the National Pharmacovigilance Programme (2004) and the Pharmacovigilance Programme of India (PvPI) launched in 2010 under the Indian Pharmacopoeia Commission, significantly strengthened the national drug safety framework. Today, ADR monitoring in India operates through a structured network involving the National Coordination Centre (NCC) and the Central Drugs Standard Control Organisation. This paper reviews the history and development of ADR monitoring in India, outlines classifications of ADRs (Rawlins and Thompson classification, severity-based, onset-based, and DoTS classification), and discusses preventive, identification, management, and reporting strategies. Special emphasis is placed on pharmacovigilance in homoeopathy and its role in enhancing patient safety and evidence-based practice. Strengthening ADR reporting systems and promoting awareness among healthcare professionals remain critical for ensuring rational and safe use of medicines across all systems of healthcare.