ABSTRACT
Many drugs and their metabolites are renally excreted and accumulate in patients with chronic kidney disease (CKD), which may lead to increased toxicity and side-effects. Kidney function decreases with age so otherwise healthy elderly patients may have unrecognized CKD. Some drugs have predictable dose related effects on kidney function. Transplant patients often have a degree of CKD but the main concern is drug interactions that may affect levels of immunosuppressive drugs. Before prescribing any drug in patients with CKD, the dosage should be checked in the British National Formulary (BNF). Many drug Summary of Product Characteristics and the BNF recommend dose modifications based on the Cockcroft–Gault formula but the estimated glomerular filtration rate (eGFR) is a reasonable surrogate for this. Drug dose modification is rarely required until the eGFR falls below 60 mL/min and most renally excreted drugs only need adjustment below 30 mL/min.
