I have a dog - half poodle, half pug - who will be 7 years old on September 17. This dog means the world to me. Over the past 6 months I have watched this dog gain over 15 pounds, lose his zest for life, and go blind. A month ago, after he started walking with a slow, strange gait and started walking into walls, my vet ran a whole battery of blood tests on him. She said his symptoms sounded like a thyroid condition to her but she was a little confused about his eyesight. His pupils constricted very slowly and at different times when she would shine a light in them. After his test results came back, she called and said his thyroid levels were bottomed out on the low side. The only other abnormality he had was a slight elevation of his WBCs but she wasn't concerned by it. She put him on 0.6mg of Soloxine daily, 1/2 in the a.m and 1/2 in the p.m. Today was his recheck. He has actually gained weight, even though I feed him exactly the amount he is suppose to eat and he gets no table scraps. (I do have to watch him to make sure he doesn't eat any food my other dogs leave behind.) His pupils were reacting better today but I can see no difference whatsoever in his vision. If anything, he seems worse and is acting completely blind. My vet drew his blood again to check his thyroid levels and see if she needs to change his medicine dosage. She seems stumped by his condition and she and another vet discussed the fact that his cholesterol level was normal while his thyroid levels were bottomed out. They said that normally when a dog has hypothyroidism, their cholesterol levels are high. My vet has mentioned several times now that it could be something as serious as a brain tumor causing my dog's symptoms. She mentioned it again today, after talking about his thyroid & cholesterol levels. Have you all ever seen this happen in dogs? Thyroid out of whack, blindness, medicine not working? He isn't having seizures or anything, but he isn't the same dog he was just 6 months ago. He seems to have aged tremendously and lies around and sleeps 95% of the time. Sometimes he growls at my kids when they pet him, which is TOTALLY uncharacteristic of him. When he is awake, he is either searching for food and bumping into everything or panting like it is 1000 degrees in the house. Do you think my vet really suspects a tumor but doesn't want to break my heart by telling me this just yet? Do you think his eyesight will come back? I mentioned SARDS and both vets didn't seem think this is the case with him. I'm so sad and confused right now, I hate seeing my sweet boy suffering like this. Should I get a second opinion? This is my dog on 12/17/07, less than 7 months ago, when he was still acting "normal"