Hello Harv -
First off, glad to meet you, but sorry it's under these circumstances. I've read many stories and it appears that blasto affects each animal in its own way. It doesn't sound like you have severe dissemination. Second, you are ahead of the game with a quick diagnosis and starting treatment right away. Lots aren't that lucky. Looking back on several other dogs in our area, it's possible they died of this without being diagnosed. Hindsight and all...
We caught Dirtbike fairly early (so the vet says) and she has been on about 3 weeks of treatment. The first few days were not so bad for her, but the medicine will quickly make them very ill. The breathing is going to go from bad to worse, and you'll have many sleepless nights. Wilson3 can tell you all about it.
After the first few doses, she got really sick and her breathing went to hell. She has times when she appears lame and off balance, but gets moving and it resolves. We are treating the lesions with antifungal creams, and the small ones have disappeared - only 2 remain, almost healed. She sometimes has a watery brown discharge from her nostrils and her nasal passages are swelled & crusty. Lots of slobber. I think that a loss of smell is also keeping her appetite low. The teeth and gums appear to be sore, but she had no trouble gnawing a bone.
After 3 weeks of freaking out, I've calmed down enough to let things take their course for now. She has very little appetite, but we are feeding her Ensure Plus 2x a day (in a bottle) along with all the meat she will eat, which is not much. She drinks very well on her own. We have had to force things like peanut butter just to keep some calories in her. She's lost a lot of weight. (From 80 lbs. to about 55, which is scary.) I've stopped any other medications because the Itraconazole is very hard on the liver, and don't want to overwhelm her system.
There were times when we were sure we were losing her, but she's hanging in. Signs of improvement are VERY slow in coming, and the treatment is very long. We've had lots of ups and downs. Patience, hope, lots of love, that's about all the advice I can give you. We let her spend her days as she likes, inside or out, roaming or sleeping.
Don't take any of his time for granted, but don't give up. Wilson3 has lots of good advice and is farther into this than I am, and Wilson is getting better. As far as I can tell, it sounds like what you're going through is not uncommon. It hurts and it's sad, but you do the best you can for your friend.
Good luck and feel free to email or post - it helps to vent.
Best to you and yours,
jen