Even taking methimazole daily, Lilly’s thyroid level was over 20. She is eighteen years old and for over a year, her T4 level remained at 20 times normal levels. Regular vets recommended radiation. She howled at night and twitched with mini seizures. Herbs for 2 weeks brought her T4 to 3 and her symptoms are better too. Without increasing her methimazole (chemotherapy), she is a new cat! Hyperthyroidism is an auto immune condition and the herbs help immune modulation.