eGFR--use beyond the evidence.

The estimated glomerular filtration rate (eGFR) algorithm has some advantages over serum creatinine concentration for estimating GFR. There are a number of caveats around the use of eGFR, predominantly because it assumes subjects are of average body size and similar lean body weight. eGFR has not been validated as a safe method of adjusting drug dosing, nor as a screening test for impaired renal function in the general population. eGFR has not been validated as a robust measure of kidney function in many groups (eg, older people, inpatients, differing racial groups, obese people). eGFR is inaccurate in many settings, such as in high, low or rapidly changing GFRs. Until evidence of safety and efficacy is provided, eGFR should not be used for calculating drug doses, and use of the Cockcroft-Gault formula or other validated methods should continue.