My endo finally agreed to armour after getting my syntroid optimized about 6 weeks ago ( I go for followup bloodwork and appt) in a couple weeks. I was on 125 mcg synthroid with a TSH of 0.2 - I think. He put me on 90 of armour, thinking I would need 120, but not wanting to give me too much too soon. He told me take it like synthoid. However, other people split it and take it 2 - 3 times a day. I have been doing that, taking 1/2 in the morning and the other 1/2 around 2pm. Even though I don't think I am optimized yet, I love armour. Almost immediately, I noticed more energy and things seemed to be less foggy. My mood has also improved.
The armour website says that cancer patients need a higher dosage than the hypo patient. If you go to the armour website, go into the doctors area. It will also give the conversion rate of armour with synthroid.
Good luck with it, as I said above, I love it! I almost feel normal again and hoping my next appt will up things a bit more for perfection!