Interventions for Xerostomia and Thirst in Adults Receiving Palliative and End-Of-Life Care: A Systematic Review With Synthesis Without Meta-Analysis.

BackgroundXerostomia and thirst are among the most prevalent and distressing symptoms in palliative care, yet the effectiveness of relieving interventions in this population remains uncertain.ObjectiveTo evaluate the effectiveness of symptomatic interventions on the intensity of xerostomia and thirst in adults receiving palliative and end-of-life care.DesignSystematic review with synthesis without meta-analysis (SWiM), reported per PRISMA 2020.MethodsWe searched five databases from inception to June 2026 for randomized controlled trials. Two reviewers independently selected studies, extracted data, and assessed risk of bias (RoB 2). Given the small number of studies and incomplete reporting of dispersion measures, data were not imputed; results were synthesized narratively and structured by comparator type.ResultsSix trials (235 participants) were included. No outcome had sufficient data for meta-analysis. Of five trials evaluable for xerostomia, two favored the intervention, three showed no clear difference, and none favored the comparator. Benefit clustered in comparisons against usual care, whereas placebo-controlled trials showed no advantage of the active agent. Risk of bias was high in three trials and raised concerns in the remainder; certainty of evidence was very low.ConclusionsEvidence is insufficient for quantitative synthesis and of very low certainty. Symptom improvement appears more attributable to structured oral care than to any specific agent. Larger, better-reported trials are needed, and thirst remains markedly understudied.