Is It Safe To Take Daflon To Stop Menstrual Bleeding Before My Robotic Myomectomy?

Hello. I am 26 years old female having H/O PCOS and fibroids. I am expecting my robotic myomectomy 2 days later from today. My periods lasted for 8 days this month and yesterday there was no signs of bleeding but today(8th day) i am experiencing again menstrual bleed. My Gynecologist has prescribed me Cap Daflon 500mg TDS to stop the flow so that i can undergo my surgery safely. Is it normal to take for stopping menstrual flow? Will it have further side effects on me? Like irregular bleeding? Because i have a H/O irregular menstrual cycle after a gap of every 2 months due to PCOS.