Doctor told me that the Synthroid he gave me was the equivalent of the 4 grains of Armour I had been taking. Switching to Synthroid was the difference of night and day! Had been taking that dosage for years and doing wonderfully well! New doctor started lowering my dosage. No explanation, just "This is how we treat this Now!" Have developed confusion and amnesia, and she continues to lower my dosage even further. I do not remember what dosage I had been taking before her changes.