CrCl vs. eGFR — Which to Use When

• Drug dose adjustment: FDA labeling is mostly based on CrCl (Cockcroft-Gault) — DOACs, metformin, many antibiotics, etc.
• CKD staging and kidney disease assessment: use eGFR (CKD-EPI), the KDIGO 2024 guideline standard.
• CKD-EPI 2021 removed the race coefficient, so the same equation now applies to all patients (NEJM 2021).
• eGFR is normalized to a standard body surface area of 1.73 m² and may differ from a given patient’s absolute renal function, especially at extremes of body size.
• Estimating equations are less accurate in AKI, pregnancy, amputees, and patients with extreme muscle mass.