Effect of oral ginger on prevention of nausea and vomiting after laparoscopic cholecystectomy: a double-blind, randomized, placebo-controlled trial

Postoperative nausea and vomiting (PONV) are among the most frequent complications following laparoscopic cholecystectomy. Recently, some studies have shown ginger, as an herbal medicine, to be effective and safe in PONV prevention; however, there is no evidence of its efficacy in the Iranian population. The aim of this study was to determine the effect of oral ginger on PONV prevention after laparoscopic cholecystectomy. This double-blind, randomized, placebo-controlled clinical trial was performed on women who were undergoing laparoscopic cholecystectomy in Imam Raza Hospital, Mashhad, Iran between April and November, 2016. Patients were divided randomly into two groups of G) intervention group (n=75, received 2 capsules containing 250 mg ginger) and P) placebo group (n=75, received 2 placebo capsules) one hour before surgery. Nausea severity and vomiting frequency were evaluated at 2, 4, 6, and 12 hours after the operation. Data analysis was done by SPSS version 16.0 software with Chi-square test, Independent-sample-t-test, repeated measure ANOVA and Mann-Whitney U test. The two groups were homogenous in terms of age, gender and surgery duration. The severity of nausea was lower in the ginger group at the 2, 4, 6, and 12 hours after the operation; however, these differences were statically significant only at 2 (p=0.034) and 12 hours (p=0.043). Although the incidence of vomiting was higher in the placebo group in the 2nd and 12th hours after surgery, the number of vomiting episodes in 2, 4, 6 and 12 hours after surgery was statistically similar in the two groups (p>0.05). The nausea severity was significantly changed during 12 hours of study in both groups (p=0.001), however the nausea severity was always lower in the ginger group (p=0.078). This study demonstrated that 500mg oral ginger one hour before surgery in women who were undergoing laparoscopic cholecystectomy is effective in decreasing severity of PONV. The trial was registered at the Iranian Registry of Clinical Trials (http://www.irct.ir) with the Irct ID: IRCT2016122222218N2. The study was financially supported by Deputy of Research of Mashhad University of Medical Sciences.