Injection of Botox into the bladder is a common treatment for overactive bladder. Postoperative bladder infection is one of the more frequently reported complications of this procedure. Prophylactic antibiotics given at the time of bladder Botox for the reduction of postoperative bladder infection have not been well studied. The main goal of our study is to determine if prophylactic antibiotics at the time of bladder Botox injection for the treatment of overactive bladder in women reduces postoperative bladder infection. The investigators are proposing a study which will randomize participants into two groups - one receiving Ciprofloxacin and the other receiving placebo pills for three days following the procedure. The primary outcome evaluated will be the difference in postoperative bladder infection between the two groups. The investigators will also investigate differences in reported side effects between the two groups possibly related to antibiotic use. Follow-up will be over six weeks following the procedure.