RADIOIODINE TREATMENT OF HYPERTHYROID CATS

Thirty-two elderly domestic shorthaired cats (mean age 12.9 years) were treated with radio-iodine (I-131). The dose of I-131 administered ranged from 39 mBq to 134 mBq. Twenty-eight cats became euthyroid after treatment, one became hypothyroid and three remained hyperthyroxaemic. Two of the hyperthyroxaemic cats were successfully re-treated with I-131. Five cats died from concurrent diseases within one year of treatment. The administration of a dose of I-131 selected by assessing the severity of the clinical signs, the size of the thyroid gland(s) and the serum level of thyroxine was an effective treatment for hyperthyroidism.