The investigators hypothesize that perioperative oral administration of pregabalin would reduce postoperative pain and produce reduction in postoperative opioid consumption after anterior cruciate ligament (ACL) reconstruction . Patients are randomly assign to 1 of 2 groups. The placebo group receive placebo capsules 1 hour before surgery and 12 hours after initial dose. The pregabalin group receive pregabalin 150 mg, respectively at the same points.