My mother, age 90, took Cephalexin, 500 mg.capsules, for a very long-term urinary infection and she s now itching all over. She had told her Dr. that she is allergic to penicillin before he prescribed it, but he said, well, it just has a little in it...it shouldn t hurt you... She has now stopped taking the medication, has taken the Claritin that the Dr. advised, but says that it does not help. She is still itching, a good week after. Will the itching go away by itself? What can she do to help it to do so?