contains details of clinical pharmacology and practical guidance on the use of the various agents to lower BP in CKD patients. Information on CKD- and CVD-related indications, side effects, dosages and contraindications relevant to all commonly used anti-hypertensive agents as well as strategies to improve adherence and warnings regarding the hazards of certain combinations are also noted therein. The Work Group believed that there was insufficient new evidence to warrant rewriting the clear guidance provided in the KDOQI Guideline. However, at the request of the KDIGO Board, the Work Group summarize specific aspects of the use of antihypertensive agents in CKD patients. We outline the information that can be drawn from the known pharmacol- ogy of agents or observations in non-CKD patients, emphasizing the difficulty in extrapolating to CKD patients, especially those with advanced CKD. Given that the prescribed drug regimen commonly involves many medications, it is reasonable to use strategies that might maximize the likelihood of adherence, including the use of cheaper drugs, convenient frequency of dosing and reduction in pill numbers. This can be achieved by prescribing once-daily medication and combination pills (which are simpler to take and in some circumstances may be less expensive than the individual agents) when possible.83 Renin angiotensin aldosterone system blockers Because of its pivotal role in regulation of BP, the RAAS system is an obvious target for BP-lowering medications. Although other agents, particularly beta-blockers, interfere with the RAAS pathway, the main RAAS inhibitors are ACE-Is, ARBs, aldosterone antagonists, and DRIs. ACE-Is and ARBs. ACE-Is block the conversion of angio- tensin I to angiotensin II and the degradation of bradykinin. It seems likely that the accumulation of bradykinin leads to persistent dry cough, a recognized side effect which occurs in 5 to 20% of patients on ACE-Is. 