Kidney function: what your kidneys do and why it matters

Your kidneys quietly keep you alive. They filter waste, balance fluids and electrolytes, help control blood pressure, make red blood cells, and activate vitamin D. Together they process the meds you take. If kidneys slow down, drugs can build up and cause harm. That’s why knowing your kidney function matters for everyday health and for safe medication use.

Signs, tests, and what the numbers mean

Kidney trouble often starts subtly. Look for swollen feet or hands, more or less pee than usual, very dark or foamy urine, constant fatigue, or new nausea. These don’t prove kidney disease, but they’re signals to check.

The basic lab checks are serum creatinine and eGFR, plus urine tests for albumin (protein). eGFR estimates how well your kidneys filter blood. Rough guide: eGFR 90+ is normal for most adults, 60–89 can be normal with age but may need watching, and below 60 suggests chronic kidney disease if it persists for three months. A urine albumin test detects tiny amounts of protein that show early damage. Your doctor may order BUN, electrolytes, and imaging if needed.

Medications, dosing, and everyday protection

Many drugs are cleared by the kidneys. That means doses need changing if kidney function drops. Antibiotics, some blood pressure meds, metformin, and many others can build up and cause side effects. Always tell your prescriber about kidney problems and bring recent lab results. Never stop a medication without talking to your provider.

Avoid frequent NSAID use (like ibuprofen, naproxen, meloxicam, or ketorolac) unless your doctor says it’s safe. These can lower kidney blood flow and trigger injury, especially if you’re dehydrated or on other blood pressure drugs. Also be cautious with contrast dyes used in some scans — mention kidney issues before imaging.

Simple daily habits protect kidneys: keep blood pressure in target range, control blood sugar if you have diabetes, cut back on salt, stay hydrated but don’t overdo fluids, quit smoking, and avoid crash high-protein diets. If you take multiple meds, ask your pharmacist to review them for kidney safety and interactions.

If you have risk factors — diabetes, high blood pressure, older age, family history, or repeated urinary infections — get checked at least yearly. If labs show eGFR under 60 or rising protein in urine, your doctor may refer you to a kidney specialist (nephrologist) for focused care.

Need practical help with meds? Use this site to read about drug dosing, alternatives, and side effects, and always take test results to your healthcare visits. Small changes now make a big difference for long-term kidney health.