 [ Symptoms ] on antibioticsinhaler for bronchitis soon after starting meds terribly itchy rash behind both knees drug allergy  started antibioticsinhaler tuesday rash presented wednesday morning rash is isolated to back of knees and has not changed in appearance or area currently using hydrocortisone and gold bond creams [ Disease ] adderall and ritalin are closely related drugs that help with the symptoms of adhd however they work in slightly different ways in the brain