still at 87 it may be more critical than at 60, say. The main concern about AFib is blood
clots and stroke, and that's what the warfarin
I don't know about the side-effects you note, I don't associate any of them with warfarin, which I take at 5 mg a day.
One can eat greens, it is just necessary to be consistent so the correct dose of warfarin can be set.
I'd ask the doctor if you mother can get by with taking just an aspirin, just in case the rare AFib bout should occur.