I have a history of high blood pressure. But it has escalated to a rather extreme level. Been monitoring for last 3 weeks. Even w/meds, lowest it has been is 138/91. But as high as 175/119. Today my doctor changed my Diltiazem 120mg xt caps 1per 24hrs, to DilitiazemSR 120mg 12 hour. After I took this med, my blood pressure changed from 150/102/79, two hours later to 169/108/80, then two hours later to 186/113/80. I have asthma also, which I use an inhaler when I have an attack. I mention this because I have developed a cough tonight. I am also on 2 Lisinopril 10mg per day. How high should my BP get before I need to go to the hospital?