Problems going from cytomel only to armour

[Liz118]

Hello Dr. Lupo
I have been on 15 mcg for about 6 years due to slightly low thyroid function and depression. Overall the meds have worked well, but I tend to get sweaty sometimes. I have been seeing a new doctor and have discovered that I have hashimoto's thyroiditis (high thyroglobulin antibodies). My T4 is low and my T3 is borderline low. My doc has switched me to a combination of levo. and armour instead of the cytomel. I started on 1 1/2 grain of armour and began to feel extremely tired and freezing cold, so we upped the dosage to 2 grains. I felt a bit worse then, more tired and my skin and nails were dry, face was puffy etc, so we upped the dose again to 2 1/2 grains. I began to feel really awful. Totally exhausted, achy, and puffy. I tried some cytomel for a couple of days to see if there was a difference and I felt so much better. My doc wants me to raise my levo dosage now, so I will have more T4 in my system. But I seem to be having difficulties with T4, so I am really worried about doing this. I don't think I can function this way for too much longer. I should mention I also have low cortisol and dhea, which I am currently addressing with low doses of cortef and dhea.
My question is, why I am getting more hypo when I raise the armour dose? Why do I do much better on cytomel?
Is it simply that my body has not needed to convert T4 to T3 in so long that it will take time to learn again? Or does this mean that my body is not converting well and I should not be on T4? Is there anything wrong with taking T3 only?

Thanks

[Mark Lupo, M.D.]

the problem w/ cytomel alone is that it is short acting (in and out in 12 hours) while T4 has a long half-life -- so if T3 is used, T4 should be used in combination.  That being said I have 2-3 patients on cytomel alone but they take it 2-3 x /day (ie if 15mcg is your dose, take 5mcg 3x/day).

[Liz118]

Sorry I just realized that I meant to say that I was taking 15 mcg of cytomel...
Thanks