The purpose of this study is to determine whether etoricoxib, flavoxate, both are effective in the treatment postoperative pain after TURP.

The research hypothesis:

There is a difference in postoperative morphine consumption in the first 24 hours after transurethral prostatectomy between patients who received etoricoxib or flavoxate or both and placebo.

Postoperative pain is still a significant problem for surgical patients. Conventional use of narcotics for postoperative pain relief is not without serious side effects such as respiratory depression and sedation.There are other alternatives for postoperative analgesia as NSAIDs especially COX2-inhibitors. For some specific operation such as TURP which Foley's catheter needed to be retained for a few days,urinary anti spasmodics may help the patients to be more comfortable.

Comparison(s): There is a difference in postoperative morphine consumption in the first 24 hours after transurethral prostatectomy between patients who received etoricoxib or flavoxate or both and placebo.

Inclusion Criteria:

1. Male patient ASA physical status I-III.
2. Scheduled for an elective TURP.
3. Body weight > or = 50 kg
4. Can operate a patient-controlled analgesia (PCA) device.

Exclusion Criteria:

1. History of asthma, acute rhinitis, nasal polyps, angioneurotic edema or urticaria following the administration of aspirin or other NSAIDs.
2. Known hypersensitivity to morphine.
3. History of hepatic dysfunction.
4. Creatinine clearance < 30ml/min.
5. History of bleeding tendency.
6. History of gastrointestinal bleeding or active peptic ulcer.
7. Known case of inflammatory bowel disease.
8. Patient with severe heart failure.
9. History of coronary artery disease or cerebrovascular disease.