Originally Posted by Eastie156
T3 I've been reading isn't all that helpful in diagnosing hypothyroidism. My T3 # was in a normal range while TSH was vey high and T4 was low.
It's probably true that the T3 level is less useful for diagnosis
, but that in no way means it's unimportant. It's a very useful guide to how well replacement is working. The theory is that T3 will correspondingly rise as T4 rises, but that's categorically untrue in every case. Some people have trouble converting enough T4 to T3 for their needs and therefore need to boost the T3 level with a prescription.
Many people find that replacement of T4 only does not give them the relief from their symptoms that they'd hoped.
T3 that's merely "in normal range" does not guarantee that level is your
particular "normal". After all, your foot size likely falls within the "normal" standard range, but that doesn't mean you can comfortably wear any and all sizes within that range.