Felimazole tablets are given by mouth. Methimazole, the active ingredient, is very bitter. Felimazole comes as a coated tablet for ease of administration. Do not break or crush the tablet. Always follow the dosage instructions provided by your veterinarian. If you have difficulty giving the medication, contact your veterinarian. Wash hands with soap and water after giving the medication. Blood levels of thyroid hormone will be checked by your veterinarian at regular intervals, and the dose increased or decreased as needed. The lowest effective dose should be used. This medication should only be given to the pet for whom it was prescribed.