Safety profile of desmopressin and risk signals for hyponatremia: evidence from FAERS and CVARDD real-world databases

Desmopressin has been associated with hyponatremia-in clinical practice; however, postmarketing real-world evidence on its safety signals, susceptible populations, and time-to-onset (TTO) patterns remains limited. This study aimed to characterize desmopressin related adverse event signals in the U.S. Food and Drug Administration Adverse Event Reporting System (FAERS,2004Q1–2025Q4) and the Canadian Vigilance Adverse Reaction Database (CVARDD), focusing on hyponatremia. Signal detection was performed using four disproportionality analysis methods (reporting odds ratio, proportional reporting ratio, Bayesian confidence propagation neural network, and multi-item gamma Poisson shrinker), with concurrent positivity across all four methods required for signal confirmation. Subgroup analyses were conducted by age and sex. For cases with complete dates, TTO was calculated and modeled using the Weibull distribution. Among 19,906,480 deduplicated reports, 3,878 listed desmopressin as the primary suspect drug. The strongest signals were observed for metabolism and nutrition disorders, particularly hyponatremia-related events (e.g., Hyponatraemia, Blood sodium decreased, Water intoxication, Hyponatraemic encephalopathy), often accompanied by seizures and other serious neurologic events. Age was the main source of heterogeneity: hyponatremia-related RORs were markedly higher in patients aged ≥ 60 years. TTO analysis showed an early-failure pattern, with ~ 60% of AEs occurring within 30 days; the Weibull shape parameter β = 0.36 (95% CI 0.35–0.37) indicated a decreasing hazard over time. Hyponatremia also occurred predominantly early but remained detectable during long-term treatment (≥ 360 days). Hyponatremia-related events represented prominent reporting signals for desmopressin in spontaneous-report databases. Cross-database assessment, subgroup heterogeneity, and TTO patterns provide pharmacovigilance context for this established safety concern. These findings characterize reporting patterns and do not quantify clinical incidence or establish causality. They support continued adherence to existing recommendations for patient selection and sodium monitoring during desmopressin therapy.