My cat just had radioactive iodine therapy for his hyperthyroidism.
Before receiving this treatement he was on methimazole long enough to
stabilize his T4 levels. When his T4 levels were normal, his kidney
functions were also normal. The vet interpreted this to mean that he
was a good candidate for the radioactive iodine therapy. So we got the
radioactive iodine therapy.

When my cat arrived for his therapy, his kidney functions were normal.
He was tested right before he left the facility approximately eight
days later, and his CUN and creatinine levels were significantly
elevated at that time, according to the tests.

I learned the test results tonight. Now I'm afraid that, in attempting
save my cat's life, I've damaged his kidneys beyond repair. I was told
to have his kidney function checked again next week by my vet. The
ironic thing is, my cat acts like he never felt better in his entire
life. And he looks better, too, since his coat is soft and smooth and
no longer rough and disheveled looking, as is characteristic with
hyperthyroid cats.

I wish I could undo what I've done.

Steve