My father is a kidney patient whose serum creatinine level is 6.1 and pottasium 5.6. His regular physician advised him to take the Irbesartan USP 150mg every morning & Ramipril 5mg every night & morning. But some other doctors say that it is harmful for kidney patient whose cratinine level is more than 2.2. Is it true? My father is taking these drugs for about 2 years.