I purchased Methimazole for hyper thyroid in my cat. He did fine on the bottle from Walmart. I purchased a bottle from here and his thyroid test was very high again. I wonder if the medicine potency was damaged somehow. Control number on the bottle is: *******; exp date is feb 2017. Anyone else have this problem? Just received a second bottle with a different control number, but have to spend another 100 dollars to get my cat tested in 2 weeks! My email is: *******@yandex.com