Hi, I have one young hen in a similar circumstance. She is very lethargic, runny nose, but not sounding wheezy, just keeps falling asleep when out running around with the others. So, we brought her in a couple of days ago and went to the feed store, my very experienced fellow there gave me Oxy Tetra-A. He is an egg farmer himself. He said it works for cocci as well. We have been using it as a drench for "Peppercorn" and she seems to be improving. We have mixed up some medicated chick feed with probiotic yogurt and hand feeding her that as well as her medication and lots of water with a syringe. Some folks say to turn them over, etc. to get the water in to them, but she just licks it off the syringe. Check and see if your chicken has hot legs, she did, so we have been treating her like she has a fever and cold. Today she ate most of a cooked, scrambled egg and will get her meds again tonight. She is still laying, but you must remember not to eat those eggs. We save them to feed back to her. If you are worried about the rest of your friends, put 1 tablespoon per gallon of water and give it as a preventative for 5 days. Again no eating those eggs and for another 5 days after the treatment.