What Causes Runny Nose, Cough Along With Hives On Torso And Back?

My 8 year old daughter has had cold symptoms for about a week; runny nose, sneezing, slight cough. She never had a fever or pain anywhere. She has since developed hives on her torso and back. Benedryl helps a lot. When she itches the spots they get worse. Could this be a post viral rash? Thank you so much!