Ketorolac Tromethamine USP For Compounding (API)Ketorolac Tromethamine USP is the active pharmaceutical ingredient (API) used in the production of pain relieving medications. It is a non steroidal anti inflammatory drug (NSAID) that works by blocking the production of certain natural substances in the body that cause inflammation, pain, and fever. It is commonly used to treat short term pain, such as post operative pain or pain from injury, and is available in both oral and injectable forms.