What Causes Itchy And Painful Rashes And Swelling Of Ankles?

i am female, 67 yrs old. i am taking diltiazem for almost 6 yrs now. for sometime my bp shoot up to 145/85(one day only) my doc increase the diltiazem to 2 in the morning 2 inthe evening. i took lisinopril but stopped it when rashes appears and my ankle swells . my diltiazem was decreased to 1 in the morning 1 in the evening.still swelling of ankle and rashes did not dissappear. the diltiazem was then decreased to only 1 a day. but still swelling and rashes are not disappearing so my doc told me to stop taking diltiazem. is there a significant affect on my blood pressure rate? my rate since i took diltiazem is going normal. only the problem is the swelling and rashes. the rashes are so itchy and painful that i cannot sleep at night. its all over my body now. around 10 red, itchy, painful rashes. thank you for your advice