Renoprotective vs. Antihypertensive Dosing of Renin–Angiotensin System Inhibitors in Chronic Kidney Disease: Analysis of Summary of Product Characteristics of Medicinal Products Authorized in Poland

Introduction: Renin–angiotensin system inhibitors are central to antihypertensive and nephroprotective treatment in chronic kidney disease. However, renal dosing information in Summaries of Product Characteristics (SmPCs) may differ between products and may not reflect current kidney function assessment. Objectives: We systematically evaluated dosing recommendations for single-component ACE inhibitors and angiotensin receptor blockers authorized in Poland, focusing on renal impairment and nephroprotective indications. Patients and methods: This cross-sectional content analysis included SmPCs for medicinal products classified under ATC codes C09AA and C09CA. Documents were retrieved from Polish and European regulatory sources. Data were extracted on indications, antihypertensive and nephroprotective dosing, renal dose-adjustment recommendations, renal function parameters, estimation formulas, thresholds, dose limits, and dialysis-related statements. Results: The final sample included 282 medicinal products. Hypertension was an approved indication in all products, whereas nephroprotective indications were identified in 106 (37.6%). Creatinine clearance was the predominant renal function parameter for dose adjustment, appearing in 190 products (67.4%). No SmPC used glomerular filtration rate for dose adjustment, although GFR was mentioned in 16 products, mainly in contraindications involving aliskiren. References to renal function estimation formulas were rare; Cockcroft–Gault was explicitly mentioned in a few products, while MDRD and CKD-EPI were absent. Nephroprotective and antihypertensive maximum doses were identical in most products, but differences were identified in 15 (14.2%), mainly lisinopril and benazepril. Conclusions: SmPCs for ACE inhibitors and angiotensin receptor blockers authorized in Poland show substantial heterogeneity in renal dosing recommendations. Greater harmonization and alignment with contemporary kidney function assessment would improve clinical applicability.