I took Sophie to the doctor 11 days ago for a sinus infection. Yesterday she finished a 10 day course of amoxicillin. This is what she looks like today. The pediatrician says it is most likely an allergic reaction to the medication. Apparently her daddy and uncles reacted the same way to it as kids. Poor girl even has it on her face, legs, and scalp. Treatment for hives = benadryl and time. *edited to add that Sophie also just had her MMR vaccine 11 days ago as well.