Effect of long tonicin on nausea and vomiting after microvascular decompression To observe the effect of long tonicin on nausea and vomiting after microvascular decompression. Methods Forty female patients underwent microvascular decompression with posterior sigmoid sinus approach for elective trigeminal neuralgia were randomly divided into two groups, the medication group (long tonic group) and the control group (saline group), 20 cases in each group, with preoperative intramuscular injection of long tonic 1.0 mg and saline 1 ml, respectively, to observe the effects on postoperative nausea and vomiting. Results There were 17 cases (85.0%) without postoperative nausea and vomiting and 3 cases (15.0%) with nausea and vomiting in the long tonic group, and 6 cases (30.0%) without nausea and vomiting and 15 cases (70.0%) with nausea and vomiting in the control group, with significant differences between them (p<0.05). Long tonic reduces the incidence of nausea and vomiting after posterior sigmoid sinus access microvascular decompression for trigeminal neuralgia. ? Microvascular decompression; long tonicin; postoperative nausea and vomiting; trigeminal neuralgia