We are also taking Fluco. As mentioned earlier Sadie's urine test came back negative, but her respiratory symptoms got much worse several hours after starting the Fluco. She had her first dose around noon that day and by 8pm or 9pm I started seeing enough change in her respirations that I took her to the emergency vet. She stayed the night, and was a little better on Thursday. We saw our regular vet and he told me her resp might get worse to the point that she might need some steriods - to watch her closely and let him know if she did get worse. Friday evening she started getting really bad. That's when I almost lost her. I gave her prednisone at home as a last ditch effort.
I was never told at the vet's on Wednesday (the day of tentative diagnosis and start of treatment) that the meds would make her worse. (I didn't see my normal vet that day, he was off). I was told to "start these meds, we'll send the urine off. She'll be on the meds for at least 3 months. Come back each month and pick up a refill. If you have any problems, just call us". Not until I saw my regular vet on Thursday did I even know she could die from Blasto. The 1st vet told me that the fluco might not work, and if it didn't then we would have to switch.
I know I've told my story a thousand times it seems, but I want you all to know I truely believe that the steriods saved her life that night. Keep that in mind if you feel like your dog needs them, then don't hesitate. Yes they do supress a dog's immune system, but we are talking short-acting steroids here. It won't be supressed that long, and maybe not very much at all. And also keep in mind that with steriods they get very thirsty, so give them as much water as they want. They will retain some fluids and bloat up a bit - and that is also temporary. Just keep in mind that the additional fluid retention can make breathing a little more difficult as well. They feel like you do when you eat Thanksgiving dinner. Just cut down on the sodium for a few days while they are on it.