An evaluation of the efficacy of licorice gargle for attenuating postoperative sore throat: a prospective, randomized, single-blind study

Postoperative sore throat (POST) contributes to postoperative morbidity. Licorice has been used as an expectorant in cough and cold preparations. In this study, we evaluated the efficacy of licorice gargle for attenuating POST.

Forty adults (18-60 yr), ASA physical status I and II of either sex, undergoing elective lumber laminectomy were randomized into two groups of 20 each. Group C: received water; Group L: received 0.5 g licorice in water. Both groups received a 30 mL mixture for 30 s, 5 min before anesthesia which was standardized. The incidence and severity of POST at rest and on swallowing and side effects were assessed at 0, 2, 4, and 24 h, postoperatively. Severity of POST was assessed by visual analog scale (between 0 and 100 mm; where 0 means no sore throat and 100 means worst imaginable sore throat). Postextubation cough was assessed immediately after tracheal extubation. Data were analyzed by Z test and Fisher's exact test. P < 0.05 was considered as significant.

POST (incidence and severity) was reduced in the Group L compared with Group C at rest and on swallowing for all time points (P < 0.05), except that the severity of POST at rest, at 24 h, was similar in both groups (P > 0.05). Postextubation cough was reduced in Group L compared with Group C (P < 0.05). There was no difference in side effects between groups (P > 0.05).

Licorice gargle performed 5 min before anesthesia is effective in attenuating the incidence and severity of POST.