It would be a good idea to have your aldosterone/renin levels checked prior to starting Florinef, because once on it, you get false low levels of aldosterone/renin. However, so many labs/offices don't do the test right. It's really amazing. Your supposed to lie in a quiet room and have your first draw and then have a second draw when standing. The sample has to be put on ice immediately and processed by specific criteria. I took Florinef .1mg since 2003. When I started having High Blood Pressure and edema in my left leg a few weeks ago. I just stopped it. I can't tell a difference taking it or not taking it. The only thing is that I have stopped peeing so much since I stopped, but that doesn't make any sense to me (regarding the Florinef)