Sorry, that last line should have read, "with a T4 only type med, but requires the addition of meds with T3. "
I would only suggest that your wife and daughter should make sure that they are going to a good thyroid doctor. By this I mean one that will treat them for their symptoms, by testing and adjusting levels of the actual, biologically active thyroid hormones (free T3 and free T4, not total T3 and total T4), with whatever type of medication is necessary to relieve symptoms, without being constrained by resultant TSH levels. Free T3 is the most important because it is at least 4 times as active as FT4, plus FT3 correlates best with hypo symptoms. TSH is a pituitary hormone that is affected by so many variables that it is inadequate as a diagnostic, by which to determine medication dosage. TSH also does not correlate very well at all with hypo symptoms.
If you would like to post their past thyroid test results and reference ranges, members will be glad to help interpret.
So if your wife and daughter are feeling fine and don't have any hypo symptoms, then I would just make sure that you insist on testing for FT3 and FT4 at the next doctor appointment, in order to know the levels when they are feeling good. If they still have symptoms, then testing and adjusting FT3 and FT4 will be required to relieve symptoms. Many members here report that symptom relief for them required that FT3 was adjusted into the upper part of its range and FT4 was adjusted to at least midpoint of its range. Sometimes this cannot be accomplished with a T$ only type med, but requires the addition of meds with T3.
bumping this up for others to post.......