Are your hypothyroidism symptoms under-treated?

Many patients that take T4 (synthroid vs levo-thyroxine) for hypothyroidism but sometimes patients still feel poorly.  While it is true that the body should convert T4 to the active form T3 all on its own. 

There are people who simply do not make this conversion well and still feel poorly despite the T4 supplementation.  This is why by supplementing with small amounts of T3, some people may find improvement in their symptoms despite having been told in the past that their lab values were normal and T3 is not needed. 

Medications like NP thyroid and armour thyroid have a combination of both T3 and T4.

Bunevičius, R. 1999. NEJM. Effects of Thyroxine as Compared with Thyroxine plus Triiodothyronine in Patients with Hypothyroidism.340:424-429