This chapter describes drugs acting on uterus, which include oxytocin, isoxsuprine, carboprost, danazol, methylergometrine, and valethamate. Adjunct in abortion, postpartum hemorrhage, labor induction, oxytocin challenge test for evaluating of fetal distress are the indication of oxytocin. Cephalopelvis disproportion, abnormal presentation of the fetus, hydraminios, multiparae, previous cesarean section or other uterine surgery, hyperactive or hypertonic uterus, and uterine rupture are the contraindications of oxytocin. Endometriosis, benign breast disorders, hereditary angioedema, gynecomastia, preoperative thinning of the endometrium, and menorrhagia are the indication of danazol.