I'd also think the high BP is due to renal failure. I've been on Lisinopril for about 19 years as my failing kidneys raise blood pressure. I was also told that taking the blood pressure tablets would help protect my kidneys. But the strange thing is that last month when my already poor functioning kidneys became even worse, my renal specialist said I had to stop taking the blood pressure tablets until my kidney function improved. Fortunately my kidneys have returned to my "usual" level and I'm now back on the blood pressure tablets.