Suggest Medication For Spots On Upper Thigh Which Looks Like Mosquito Bite

My daughter, 15, 115 pounds, 5'5, had what appeared to be a misquito bite on her upper thigh, within a day it got the size of a quarter, we put hydogren peroxide on it, and neosporin, it appeard to dry up, but within next week these bites spread down her leg and up onto back, each one gets bigger by the day and some ooze, they do not itch, I took her to doctor which he looked at her and said it was staff, they put her on oral anitbiotics, and topical cream, twice a day, she says the cream burns, thats been 3 days ago, when should we notice the spots getting better?