Diaper Rash from Antibiotics

Okay okay. I know technically this is supposed to be a "stay at home and work" blog but I am writing to seek advice from other stay at home moms. My son is on a round of antibiotics for 10 days (today is day 4). His rear end and delicates are so red that he won't sit down and is fearful of having his diaper changed. I know this is common from antibiotics and I have the prescription nystasin cream for diaper changes. Does anyone have any home remedies that can help me out?