Lab Values for Nurses Practice Test 2026 – Comprehensive Exam Prep

eGFR measures how well the kidneys are filtering waste from the blood, and it is normally about 90 mL/min/1.73 m² or higher. This threshold matters because it helps determine kidney health over time and guides how we dose many medications that are cleared by the kidneys. When the eGFR is in the normal range, most drugs can be given at standard doses, but as the eGFR falls, dosing adjustments or even avoiding certain drugs becomes important to prevent toxicity. The typical signs of reduced function start with ranges below 60, which indicate CKD and require dose changes and closer monitoring. Very high eGFR values (hyperfiltration) aren’t typically considered a normal baseline for healthy kidney function and can occur in conditions like early diabetes, but they don’t represent a standard normal functioning state.