Preoperative Oral Administration of Kikyo-To, a Kampo Medicine, Alleviates Postoperative Sore Throat: A Prospective, Double-Blind, Randomized Study.

Objectives: This study aimed to determine the efficacy of Kikyo-To (KKT), a Kampo medicine, in treating postoperative sore throat and nausea.

Design: This randomized, controlled, double-blind study was conducted among two groups of women who were scheduled to undergo benign surgery under general anesthesia. All patients had a physical status of 1 (normal, healthy patient) or 2 (patient with a mild systemic disease), according to the American Society of Anesthesiologists criteria. Patients were randomly assigned to the KKT group or the placebo (control) group.

Intervention: Before surgery, the KKT group received KKT (5.0 g) mixed with jelly, while the placebo group received only jelly. Patients and the evaluator were blinded to the treatment status.

Outcome Measures: At 0, 3, and 24 hours after anesthesia recovery, an investigator (also blinded to the treatment status) recorded the incidence and severity (using the Numeric Rating Scale [NRS]) of sore throat and nausea.

Results: The incidence of sore throat was significantly lower in the KKT group than in the control group immediately after surgery (p < 0.05). The severity of sore throat on the NRS was significantly lower in the KKT group than in the control group immediately and 3 hours after surgery (p < 0.05). In contrast, the incidence and severity of nausea did not differ significantly between the two groups.

Conclusions: KKT administration before general anesthesia did not alleviate postoperative nausea but effectively decreased the incidence and severity of postoperative sore throat in women undergoing benign surgery.