BackgroundDexamethasone has been shown to alleviate pain, yet the optimal dosing and safety profiles remain unclear. This study aimed to evaluate the analgesic efficacy and impact on sleep quality of three different doses of intravenous dexamethasone in patients undergoing total knee arthroplasty (TKA). MethodsIn this randomized, triple-blind, clinical trial, we assessed the analgesic effects of three doses of intravenous dexamethasone (4 mg, 8 mg, and 16 mg) in adult patients who underwent TKA. Pain was measured using the visual analog scale (VAS) at 1, 12, 24, and 48 hours postoperatively, and sleep quality was assessed two weeks post-surgery. ResultsA total of 90 participants were enrolled in the study, with 30 participants in each dosing group. The mean VAS scores at 12, 24, and 48 hours postoperatively showed significant improvement from baseline in all groups. Notably, the 16 mg and 8 mg dexamethasone groups demonstrated significantly greater pain reduction compared to the 4 mg group (P < 0.05). Additionally, sleep quality significantly improved in the 16 mg and 8 mg groups (P < 0.05). ConclusionDexamethasone at doses of 4 mg, 8 mg, and 16 mg effectively reduces pain and enhances sleep quality in patients undergoing TKA, with the 16 mg dose showing the most pronounced effects at 12, 24, and 48 hours postoperatively.