Join Date: Jun 2008
Location: northern Minnesota
Since I am not made out of money, this is the way I handle blood retesting during the med dose adjustment period. I check only Total T4 three weeks after every dose adjustment UNLESS the cat is exhibiting symptoms that indicate a possible kidney or liver problem (inappetance, vomiting, diarrhea, lethargy, weakness, yellow mucous membranes, etc.). Assuming none of these symptoms are present, I wait until the TT4 has lowered enough that I can reasonably expect the next retest to show euthyroid, then I request a full blood chemistry, TT4, and CBC for that final test.
Please note that normal TT4 for an older cat is at the lower end of the reference range, so don't be satisfied with a TT4 in the upper half of the reference range UNLESS the cat also has renal insufficiency (I'll explain more about the connection between hyperT and CRF later).