The effect of oral stimulants on thirst of patients in the post-operative period: a systematic review and meta-analysis of randomized controlled trials.

INTRODUCTION: Thirst is a prevalent symptom during the immediate postoperative period. It appears that the utilization of oral stimulants is a primary method for managing these symptoms. This study aimed to conduct a systematic review of studies that assessed the impact of oral stimulants on patients' thirst during the immediate post-operative period. METHOD: A thorough search was performed on six electronic databases, including PubMed, Web of Science, Scopus, Cochrane Library, CINAHL, and Embase, from each database's earliest inclusive dates to 17 September 2025. No limitations were placed on the language of the studies included in this study. The risk of bias assessments were executed utilizing the Cochrane Risk of Bias 2 tool. A meta-analysis was executed, with additional subgroup analysis. The publication bias was examined using funnel plots and Begg and Egger's test. A sensitivity analysis was conducted utilizing the leave-one-out approach. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach was employed to assess the certainty of the evidence. RESULTS: Data were collected from 14 randomized clinical trials (RCTs) with 1289 patients for meta-analysis. Our meta-analysis showed that the pooled SMD for thirst intensity difference across groups was - 1.38 (95% CI: -1.92, -0.84). Included studies exhibited significant heterogeneity (I2 = 94.81%). The subgroup analyses in two subgroups (starting point for evaluations and baseline inequality) justified the high heterogeneity. The effect was derived from three oral stimulants (menthol, cold water, and ice), and when analyzed individually, menthol and cold water reached significance in reducing thirst intensity compared with controls. Moreover, our study has highlighted the likelihood of publication bias for thirst intensity. The results of the GRADE evaluation demonstrated a low level of evidence regarding the severity of thirst. CONCLUSION: Based on our study's findings, interventions involving menthol, cold water, and ice have significantly decreased post-surgical thirst intensity. Obtaining more robust conclusions requires that subsequent research adopt standardized methodological practices, thereby reducing methodological heterogeneity. REGISTRATION: The study protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO) at the National Institute for Health Research (No: CRD42024599788).