Quoting Bailee & Delilah's Mommy:" Okay, I know my friends son had croup and they only got antibiotics, which I have that. And her doctor ... [snip!] ... just no fever. She acts fine till night time when she coughs crazy. Shes had it since saturday and its no thatt bad anymore."
croup is viral. They wouldn't give antibiotics just for that. There would have to be some sort of bacterial infection on top of croup. A steamy room, or cool air if it's cold by you will help. If it's super bad they can give you steroids for it that will help (kid sized, not athlete sized)