6.3: We suggest that an ARB or ACE-I be used in children with CKD ND in whom treatment with BP-lowering drugs is indicated, irrespective of the level of RATIONALE This recommendation is based on published experience with these agents in children with hypertension, showing the drugs to be safe and effective in lowering BP and to confer a benefit for slowing CKD and reducing urine protein levels in adults with CKD. However in teenage girls, pregnancy testing and the use of birth control prior to and during ACE-I/ARB therapy need to be considered. Additionally, as mentioned above, discontinuing these agents during episodes of diarrheal illness and dehydration should be considered.338 ACE-Is or ARBs should be the preferred choice in treating proteinuric CKD (see Chapters 3 and 4). Multiple studies in adults with CKD have shown renoprotection with the use of ACE-Is or ARBs. RAAS antagonists preserve kidney function not only by lowering BP but also by means of anti-proteinuric, anti-fibrotic, and anti-inflammatory properties. In the ESCAPE trial described above, on the basis of previous research in adults, the children in both arms of the intervention received a fixed, maximum dose of the ACE-I ramipril.323 Further BP lowering was achieved through the addition of other medica- tions at the discretion of the local provider. Others have recommended ACE-Is or ARBs as first-line agents in treating children with CKD and high BP,339 particularly in those with proteinuria.340 The recently released European Society of Hypertension guidelines337 assert that it is reasonable to recommend agents blocking the renin angiotensin system as first choice in proteinuric, and also in non-proteinuric patients with CKD. How- ever, limited direct evidence from clinical trials is available with which to assess the efficacy of RAAS in children with CKD. 