The use of medical management of ectopic pregnancy has become an accepted alternative to surgical therapy. Methotrexate, a folic acid antagonist, is the most widely studied agent. The most commonly used protocol consists of methotrexate 50 mg/m2 of actual body weight. Assessment of human chorionic gonadotropin (hCG) levels is repeated on days 4 and 7. Repeat methotrexate dosing is performed for hCG drops <15%. Contraindications include hemodynamically unstable patients or those with elevated liver enzymes, low white blood count, or abnormal renal function. hCG levels are most predictive of success. A success rate of above 90% is achievable.