Doctors commonly assess kidney health using blood and urine tests.

A blood test can measure creatinine, which is used to estimate the glomerular filtration rate (eGFR), an important measure of kidney function.

Urine testing can look for albumin or other proteins, blood, and other abnormalities.

These tests can identify kidney problems even when a person feels completely normal.

When Should You Seek Medical Attention?

Don't wait if you experience very little or no urine, severe swelling, significant shortness of breath, persistent vomiting, severe weakness, confusion, or other rapidly worsening symptoms.

Blood in the urine, persistent foamy urine, unexplained swelling, or ongoing changes in urination should also be discussed with a healthcare professional.

If you already have kidney disease, diabetes, high blood pressure, or another condition that increases kidney risk, follow the monitoring schedule recommended by your healthcare team.

The Bottom Line

Your kidneys perform essential work every minute, yet kidney disease can remain surprisingly difficult to notice in its early stages.

Changes in urination, persistent swelling, foamy urine, blood in the urine, unexplained fatigue, nausea, itching, muscle problems, confusion, and flank pain can occur with kidney or urinary conditions—but none of these symptoms alone proves that your kidneys are failing.

The most reliable way to assess kidney health is through medical evaluation and appropriate blood and urine testing.

So don't panic if you experience one of these symptoms, but don't repeatedly ignore symptoms that persist or worsen either.

Your body may give you clues, but laboratory testing—not a social-media checklist—is what can actually tell you how well your kidneys are functioning.