Incidence, Causality, Severity, and Preventability of Cutaneous Adverse Drug Reactions in a Tertiary Care Teaching Hospital in South India: A Prospective Observational Study

Abstract

Background: Cutaneous adverse drug reactions (ACDRs) are the most frequently reported form of drug-induced injury, yet spontaneous reporting captures only a small fraction of cases in India relative to high-income settings. Data from tertiary dermatology units remain limited.
Methods: A hospital-based, prospective, observational study was conducted over 12 months (December 2023–December 2024) in the outpatient and inpatient wards of the Department of Dermatology, Venereology and Leprosy at King George Hospital, Visakhapatnam. Patients above 18 years receiving at least one allopathic drug were enrolled after informed consent. Causality was assessed with the WHO-UMC scale and Naranjo’s algorithm, severity with the Hartwig and Siegel scale, and preventability with the Schumock and Thornton criteria.
Results: Seventy-one ACDRs were documented in 71 patients. Men accounted for 43 cases (60.6%) and women for 28 (39.4%); reactions were most frequent in the 31–40-year age band (21 cases, 29.6%). Oral drugs accounted for 49 reactions (69.0%), followed by intravenous (18, 25.4%), intramuscular (3, 4.2%) and topical (1, 1.4%) agents. Diclofenac (n=5), piperacillin-tazobactam (n=4) and methotrexate (n=4) were the most frequently implicated individual agents; by class, NSAIDs (19, 26.8%) and antibiotics (15, 21.1%) predominated. The WHO-UMC scale classified 55 reactions (77.5%) as probable and 15 (21.1%) as possible; Naranjo’s algorithm classified 53 (74.6%) as probable. Under the Hartwig-Siegel scale, 30 reactions (42.3%) required hospitalization and 3 (4.2%) were life-threatening; 53 (74.6%) were judged definitely preventable under the Schumock-Thornton criteria. All 71 patients recovered fully, with no fatalities.
Conclusion: NSAIDs and antimicrobial agents administered orally were the leading causes of ACDRs in this cohort, and three in four reactions were judged preventable. Structured causality, severity and preventability assessment at the bedside, paired with closer prescribing oversight for these two drug classes, could meaningfully reduce the burden of drug-induced skin injury in similar tertiary-care settings.