Renal Drug Dosing by Creatinine Clearance

Many renally-cleared drugs are dosed in creatinine-clearance bands, commonly above 50, 30-50, 15-30, and below 15 mL/min, with the dose lowered or the interval lengthened as clearance falls. Calculate the patient's clearance first, then apply the drug-specific threshold.

Reviewed and approved by Dr. Rishi Kumar Kafle, MBBS, MD, FASN. Always confirm against the label.

How Renal Drug Dosing Works

When a drug is cleared by the kidneys, falling kidney function slows its elimination and lets it accumulate. Renal dosing corrects for this in one of two ways: reducing each dose or extending the interval between doses. Drug labels translate this into discrete creatinine-clearance bands, and the same four cut-points recur across drug classes:

• Above 50 mL/min: normal renal function for most agents; the standard dose usually applies.
• 30-50 mL/min: mild to moderate impairment; many drugs call for a first dose reduction or a longer interval here.
• 15-30 mL/min: moderate to severe impairment; deeper reductions, and some agents become contraindicated.
• Below 15 mL/min: kidney failure or dialysis; many drugs are avoided, and dialysis timing drives the dose for those that are not.

These bands are guides, and the boundaries between them are not sharp. A patient at 31 mL/min is clinically similar to one at 29 mL/min, so the trend, the indication, and the drug's therapeutic window matter as much as the single number. Always read the specific drug label rather than assuming the bands above.

Why Creatinine Clearance, Not eGFR, for Dosing

Most drug labels were validated against Cockcroft-Gault creatinine clearance, expressed in mL/min. That is the unit the dosing thresholds were derived from, so it is the unit to use when applying them. The CKD-EPI 2021 equation reports eGFR in mL/min/1.73m², a value indexed to body-surface area. That makes it excellent for CKD staging, but it is a different quantity from the one most labels reference. The two can differ substantially in small, large, elderly, or frail patients. For the full reasoning, read CrCl vs eGFR: which to use and when.

A handful of agents are the exception and are labelled by eGFR rather than creatinine clearance, notably metformin and the SGLT2 inhibitors (such as dapagliflozin and empagliflozin). Their modern labels and guideline thresholds are written in eGFR. Each drug page states which estimate its thresholds use. For how the FDA's March 2024 guidance groups mild, moderate, and severe impairment in mL/min, see the FDA renal impairment categories.

How to Use the Class Index

The table below groups all 93 drugs into 12 classes. Open a class to see every agent in it and its CrCl-threshold table, or go straight to a drug in the A to Z index. Each drug page links back to this hub and to the creatinine clearance calculator, so the workflow is always the same: estimate the clearance, find the band, apply the label.

Monitoring and Re-estimation

Renal doses need re-estimation because kidney function is not static. In acute illness, after a new nephrotoxic agent, or with shifting fluid status, re-estimate clearance and re-check the dose: a value calculated on admission can be wrong by the next day. For agents with a narrow therapeutic window, such as vancomycin and the aminoglycosides, confirm with drug-level monitoring rather than relying on the estimate alone. Watch too for nephrotoxic combinations that can worsen function and shift the patient into a lower band mid-course.

Drug Classes

All 93 Drugs A to Z

This index lists every drug page in the registry in alphabetical order. Agents whose labels use eGFR rather than creatinine clearance are marked (eGFR), and agents with no CrCl dose band are marked (no band).

Dosing Tools

• Calvert formula (carboplatin) calculator
• Vancomycin AUC dosing calculator
• Nephrotoxic drugs overview