Effect of indomethacin on pain relief after thoracotomy. The effect of indomethacin on postoperative pain was studied in 60 adult patients undergoing thoracotomy in a prospective, randomized, double-blind manner. Patients receiving indomethacin required significantly less opioid after operation and had significantly lower pain scores compared with the control group. Pain on movement and on coughing were reduced also. No major adverse effects were encountered. 