I agree with oldtimegator on this one. Mostly because this bird still has an excellent appetite, and is drinking well, also. She appears healthy in every other sense of what "healthy" is to me. I also agree that you should start with as low a strength of medicine as possible and work your way up. UNLESS you've got a bird that's extremely compromised in some way (which is how my splash marans that's been on Gallimycin for 8 days now is....she's picking at her feed, but not eating or drinking on her own. This is obviously very serious, and I felt called for something strong).
Thus, I'd decided to start this bird, Carmen, on Terramycin as soon as I got home from work. However, when I checked on her last night, the swelling around her eyes actually had subsided a bit, and I noticed the rest of the birds in that pen have the same issue, thought not nearly as bad as Carmen. They are all eating & drinking, and otherwise seem healthy (with the exception of a few sneezes now and then, but nothing compared to the sneezing I heard 4 days ago). So, it may have been a bad decision, but I decided after much thought to put Carmen back in with the others. I figured, it's obvious they all have what she's got, so if it doens't get better, I'll end up treating them all anyway.
With all I have on my plate with my juvenile pen and the splash marans pullet, with my adult layers (Carmen's pen), I've decided to take a wait-and-see attitude, watching closely for any additional signs or symptoms.
It's SO frustrating, Chickenmonk, because I work so hard to make sure their coops and runs are clean, make sure they have fresh water with vitamins/minerals, are getting good feed, oyster shell, and grit free choice, they get healthy treats, etc. Lately, it just feels like it's not worth it. So, wait & see for the big girls. They're all 17-18 months old, should have good natural immunities by now, so I'm hoping they will be able to fight off whatever this is. Sigh....
Oh, on the cool mist humidifier - I've been trying to find one on
eBay, but keep getting outbid. It's probably BYC folks all doing the same thing I'm doing!