Re: Supplement Info needed
First I'll say, the percentages are only general guidelines and don't have to be adhered to religiously. I feel fine when my FT4 is at 40% and FT3 at around 70-75%. That's unbalanced, and FT4 is too low on average, but I feel ok that way.
That said, your mother doesn't feel ok that unbalanced. Yet, I would agree that raising her Armour dose will put her FT3 too high... and that's not good for an older person.
It is perfectly possible to add a little synthetic T4 to her Armour dose. I've seen many people on this board treated that way. Finding the right balance is trial and error, though, just as it is in any hypoT treatment. Her Armour will probably need to be cut back a bit in order to adjust for the T4. Since she is a senior, any change should be subtle and well thought out, so as to avoid stressing her heart. You don't want to throw her into atrial fibrillation.
In case you aren't aware, Armour contains 38 mcgs of T4 and 9 mcgs of T3 per 60 mgs. T3 is 4 times as potent as the same weight of T4. And 60 mgs of Armour is the approximate equal of 75 mcgs of T4. Those facts should help you sort out what you need to ask of an MD.