The medication typically found in most common medicated chick starter is not an antibiotic, it is Amprolium which is simply a thiamin blocker to help control overgrowth of the coccidia protozoa while the chicks develop their own immunity. There are some feeds that contain Bacitracin but they usually are not commonly sold at feed stores and are more for commercial type situations. But one should always check labels to be sure of what they are purchasing.