Four grid table.

Background Spironolactone, a potassium-sparing diuretic, is commonly prescribed for conditions such as heart failure, hypertension, and hyperaldosteronism. This study aims to explore and analyze the safety profile of spironolactone by examining adverse event reports from the FDA Adverse Event Reporting System (FAERS) database. Methods This study conducted a retrospective pharmacovigilance analysis using FAERS data (2004 Q1–2024 Q3). Adverse drug events (ADEs) related to spironolactone were identified and categorized by system organ class and specific adverse events. Statistical methods such as Proportional Reporting Ratio (PRR), Reporting Odds Ratio (ROR), Bayesian Confidence Propagation Neural Network (BCPNN), and Empirical Bayesian Geometric Mean (EBGM) were employed to detect potential safety signals. Results A total of 8,566 ADE reports were associated with spironolactone, with 2409 preferred terms and 25 system organ classes showing significant disproportionality. Notable rare ADEs identified included endometriosis male (n = 7; ROR 13615.84), 5-alpha-reductase deficiency (n = 5; ROR 1620.81), bulbospinal muscular atrophy congenital (n = 6; ROR 402.42) and double-hit lymphoma (n = 5; ROR 243.12). Conclusion While most findings were consistent with spironolactone’s known effects, new signals, including a potential link to male endometriosis in high-risk groups, were identified. Further research is needed to confirm these findings and improve long-term safety assessment and clinical management.