What Causes Itching Along With Blotchy Skin On Legs, Thighs And Chest?

I had total hip replacement on 1-19-15. Don t know if the itching is related to surgery. Have titanium hip. At end of February I started itching, legs, thighs, chest, arms. When active skin is blochy red, lots of red dots. Taking baby aspirin and generic cholesterol, calcium with vitamin D.