Rachel,

I do know that Armour thyroid has both T4 and T3 (the biologically active form of the thyroid hormone). Many people do just fine on a T4 replacement only but others have a hard time converting T4 to T3 and need to supplement with a small amount of T3. I really need this as my T3 levels are low but my body can not handle much because my adrenals are stressed. Usually stressed adrenals are reflected as low cortisol but I have read that cortisol levels elevate before a total crash. I know cortisol levels vary throughout the day. Weak adrenals might have been the reason you could not handle Armour thyroid. My holistic doctor is very good at sorting all of this out and he has put together a chart on his website so one can try to determine if their symptoms are due to weak adrenals or low thyroid. Here is a link to the chart http://www.drrind.com/scorecardmatrix.asp

Hope some of this helps.

--Judy