(Dechra Veterinary) Felimazole Coated Tabs for Cats are used for the treatment of hyperthyroidism in cats. Felimazole Coated Tablets contain methimazole. The starting dose of Felimazole is recommended at 2.5 mg administered every 12 hours. Following 3 weeks of treatment, dosage may be adjusted. Do not use in pregnant or lactating queens or male cats intended for breeding. Methimazole.