However, non-dihydropy- ridines might interfere with the metabolism and excretion of chapter 5 http://www.kidney-international.org & 2012 KDIGO the CNIs cyclosporine and tacrolimus, as well as the mTOR inhibitors sirolimus and everolimus. When renal transplant recipients are prescribed non-dihydropyridine calcium- channel blockers, careful monitoring of CNIs and mTOR inhibitors blood levels is required if drugs or dosages are changed. ACE-Is and ARBs are known to have acute hemodynamic effects, resulting in an increase in SCr level, and are therefore frequently avoided within the first 3 to 4 months after transplantation, when acute rejection is a strong possibility, and an increase in creatinine level can be difficult to Side effects of ACE-Is and ARBs when used soon after transplantation include increased creatinine levels, hyperkalemia, and anemia. One study showed that although 44% of patients were receiving ACE-Is or ARBs at the time of transplantation, the proportion dropped to 12% at 1 month and subsequently increased to 24% at 6 months.294 In the longer term, especially in kidney-transplant patients with persistent albuminuria, ARBs and ACE-Is should be considered. Two analyses of registry data have been published, with one showing a benefit and the other no benefit with the use of ACE-Is or ARBs for graft and patient Small trials have examined various agents to lower BP in kidney-transplant patients. One examined losartan, captopril, and amlodipine and noted no change in BP or kidney function between baseline and end of follow-up. ACE-Is and ARBs did, however, reduce the risk of proteinuria, as compared with a calcium-channel blocker308 (Supplementary Table 60 online). The Study on Evaluation of Candesartan Cilexetil after Renal Transplantation (SECRET) was an RCT of candesartan The primary outcome was all-cause mortality, cardiovascular morbidity, or graft failure. 