Hello again. My name is XXXXX XXXXX I am an experienced small animal veterinary surgeon, I will be very pleased to work with you today and will try my best to answer your question to your satisfaction.
Can you tell me did this reaction affect his skin and if so what did it look like?
I very much doubt if the Frontline would cause any problem if applied now, reactions to Frontline are very rare and there would normally be no drug interactions between Frontline and antibiotics or anti-inflammatory drugs.
No problem, very glad to have advised you ...