Marina Mickael, Eric Morris, Mollie M Roush and Inder Sehgal
Community pharmacies are increasingly receiving prescriptions from veterinarians for dogs and cats to receive human medications. However, retail pharmacists are not routinely trained in relevant aspects of veterinary-specific pharmacotherapy, such as, signs of improvement, time to improvement, drug administration techniques and potential adverse effects. Thyroid diseases in dogs and cats are treated with human-approved drugs that may be referred to pharmacies. Hypothyroidism is far more frequent in dogs, while hyperthyroidism is far more frequent in cats. Important comparative aspects of canine hypothyroidism pharmacotherapy can be summarized as follows: 1) Canine hypothyroid disease is similar to Hashimoto’s thyroiditis in humans in many of its signs and is treated using levothyroxine; 2) The doses of levothyroxine given to dogs are strikingly higher than in people; 3) A reasonable therapeutic goal is resolution of symptoms in two weeks to two months and a normal total T4 value (≈04-3.7 μg/dL). Important comparative aspects of feline hyperthyroidism pharmacotherapy are: 1) Cats usually have a functional thyroid adenoma, while people usually have an autoimmune condition referred to as Grave’s disease; 2) Common signs noticed by cat owners are weight loss and increased appetite; 3) Methimazole is used for therapy as it often is in people; 4) Clinical improvement follows in approximately 3-4 weeks; 5) Adverse reactions occur and are most often vomiting, anorexia, and lethargy; 6) Transdermal methimazole from a compounding pharmacy will be a consideration for some cats.