Just wanted warn others of the dangers when taking Fleets Phospho-Soda if you are also taking ACE inhibitors (e.g., lisinopril) for hypertension. Approximately 18 months ago I went in for a routine colonoscopy. My physical one month prior showed that my kidney functioning was fine. HOWEVER, the GI doc gave me Fleets Phospho-soda for my prep, even though I had told her that I was taking lisinopril for mild hypertension. What I did not know was there is an FDA warning issued and a "Dear Dr" letter sent to physicians warning them that, in rare cases, Fleets causes acute kidney failure in patients taking an ACE inhibitor. Within 48 hours I did, in fact, develop acute failure, which resulted in spending 11 days in the hospital and being left with permanent kidney damage. I am now a late stage 3 chronic kidney disease patient, and have to be on the renal diet for life (it is VERYdifficult and restrictive), get injections of the synthetic hormone Aranesp for my red blood cell deficiency (my kidneys no longer make the hormone necessary in red blood cell production), get occasional IV infusions of iron, and battle edema, bruising, and fatigue. Also, having chronic kidney disease increases my risk for cardiac disease and death. Despite the data, the FDA warning, and Dear Dr letter, many GI docs refuse to change their practice and STILL give Fleets to patients on ACE inhibitors WITHOUT INFORMING THEM OF THE RISK. Their justification is that "the risk is rare." This is true, but I am EXHIBIT A that it DOES happen. The thing is, it's easy to avoid the risk: either go off your hypertensive meds for a few days (ask your cardiologist if this is safe for you), or take another prep, such as Go-lytly.