"I knew we'd get some movement soon, I'm glad it was downward!" -- YES! Glad to see that 266 for you and Sammy, Sue. I'd hold that 1.0U dose to see how Sam continues to do on it.
My thinking for you and Sam, Sue, is that you need to find a dose that's giving some good numbers for him, including some blues and greens. And then when you get a number too low for you to be comfortable shooting that full dose, you'd shoot a reduced dose. But you'd return to the full dose the next cycle/shot. In effect, you'd be draining Sam's depot/shed a slight bit so hopefully the full dose could continue working for him. The current 1.0U dose may end up being too high for that, but too early to tell right now.
If you look back over Sam's spreadsheet, Sue, you'll see that he's not holding dose reductions well. And although I know consistent AM & PM dosing works best for most cats, I think it's worth trying a different approach with Sam to get him more stable. The uneven dosing (different AM & PM doses), would be as needed for Sam and not the norm. That's just a suggestion I have, Sue.
Hope you have a pleasant day.
Eva
