dbg I've been following Raggs story just like I followed Pepper's, he will tell you when the time is right, try not to miss the signs
If it were me and he still has his dignity then I would hold off for now and continue taking it one day at a time.
I was reading about Metacam and it says that it can cause diarrhea. Perhaps you could check with your Vet to see if there is another pain med that would do the trick.