The opioid-sparing effects of intravenous ketorolac as an adjuvant analgesic in cancer pain: application in bone metastases and the opioid bowel syndrome.

Side effects of morphine are common when given in titrated doses to control severe pain in advanced cancer. We report a case series of acutely ill cancer patients suffering from pain, complications of advanced disease, and opioid side effects. They were treated with intravenous (i.v.) ketorolac along with i.v. morphine using repeated dosing. Excellent pain relief with improvement in the opioid bowel syndrome was achieved. We found it possible to switch from IV ketorolac to oral ketorolac along with oral morphine for long-term pain control. Ketorolac can be well tolerated in high-dose, long-term use even in this frail patient population. An algorithm is presented for the suggested use of ketorolac as a morphine sparing agent. Potential methods for studying ketorolac further in this role are discussed.