*4.1.3 Recommended non-conventional non-steroidal anti-inflammatory drugs*

They are used in palliative medicine for the treatment of moderate and severe chronic pain, alone or in combination, including cancer pain:

*Metamizole* or dipyrone is an old non-opioid drug patented in 1922 in Germany. It has analgesic, antipyretic, spasmolytic, and fewer anti-inflammatory effects. The possibility to provoke a life-threatening agranulocytosis after long use made metamizole for a long time to be under scrutiny. It was restricted in many countries in the world, but today after relevant clinical studies, the evidence has changed. Now, metamizole is recommended as an effective pain reliever in treatment of acute pain, particularly for renal colic and acute pancreatitis. It is found in form of tablets, suppositories, and injections for IM use [47].

*Ketorolac* is the most widely used non-steroidal, anti-inflammatory drug for treatment of moderate to severe pain in adults. Its mode of action is by blocking both cyklooxygenase (COX1 and COX2) and decreasing the prostaglandin production. Its' medical use dates to 1989, predominantly for postoperative pain relief. It is found in form of tablets, nose spray, injection for IM and IV use, as well as eye drops. Its use shows many benefits. It is an efficient analgesic, an opioid sparing NSAID drug, and improves the bowel motility what makes it suitable for postoperative analgesia in abdominal and obstetric surgery. Its adverse effects limit its use up to 6 days [48].
