Hello, welcome to JustAnswer. My name is***** will be happy to help you. I am sorry to hear that Rooney is having some arthritis problems. Hopefully the medications are helping him. To answer your question, yes, he can receive both medications on the same day. There have been some reports of not using it with an NSAID because because Adequan is a heparin analog, but they have been used together a lot with no issues that I have ever seen. It would depend on how your vet feels about it, but chances are they would be okay with it. If there is any concern, it shouldn't be a problem stopping the Galliprant for one day, then restarting it the day after the injection. Please let me know if you have any other questions.