If you hear wheezing, that can be respiratory illness, could be something caught in the throat, or a number of things. I never give antibiotics for anything like that because it doesn't cure most illnesses of respiratory nature, just fixes the symptoms if it's bacterial. First of all, if you have something viral going on, no antibiotic will touch it. If it's bacterial and respiratory, you may cure the symptoms but they will most likely remain carriers. If it's just sneezing, do look up the nares with a flashlight and down the throat (a two person job, put a pencil crossways in the beak and look down there). Syringe oil into her mouth then massage gently so if there is something stuck like a piece of corn or a screw, it may be eased down.
I just had a chickie rodeo trying to catch a couple of flighty chicks to remove legbands and one's crop was pressed on, pushing something up into her throat, making her gurgle. No symptoms and if we hadn't stressed her and manhandled her, it wouldn't have even happened, but there you have it, a non-respiratory cause of an unsettling sound from a chicken. I have her in the house to calm her down and drink water and make sure she's okay, but there can be so many causes that are not even disease related. Always separate a bird in question, though, till you can figure it out.