Thyroid Problems

My 8 year old sheltie-poo was diagnosed, on the basis of a blood test, with severe hypothyroidism (her thyroid produces almost no hormone) and was placed on a thyroid hormone supplement regimen. She has responded very well to the supplement- she has lost excess weight and has regained her enthusiasm for living. Now, however, bloodwork shows that she is severely hyperthyroid, and she's been placed on a lower dose of hormone. She will have further bloodwork in 4 weeks to see how she's responding. She seems okay except for a lot of panting, which seems to be diminishing slightly as the weeks go on. I'm worried about the panting and would like to hear from anyone who has been through this process with their dog- could the panting be a result of the hyperthyroidism? :confused:

Yup, it could be. The same thing happened with my dog, Chum. His thyroid produces nothing on it's own. He would be running around and just fall over. His thyroid levels were so low it was affecting his heart. After the first month on thyroid supplements, he was hyperthyroid. It took a couple adjustments to get the dose right, but he's fine now. I'm sure your dog will be too once you find the right level of supplement.