Kidney Health Tests in California

Kidney health tests are blood tests that check how well your kidneys filter waste from your blood. They are often ordered during routine checkups or when a clinician suspects a kidney problem, such as from diabetes, high blood pressure, or certain medications.

What it measures

Creatinine — A waste product from muscle that healthy kidneys remove from blood.
eGFR (estimated glomerular filtration rate) — A calculated number that estimates how well your kidneys filter.
Blood urea nitrogen (BUN) — Another waste product that can rise when kidney function drops.
Electrolytes (sodium, potassium, bicarbonate) — Minerals your kidneys balance; abnormal levels can signal kidney issues.
Albumin or protein — A blood protein checked to help assess kidney and overall health.

Who it is for

A primary care clinician, nephrologist, or other healthcare provider typically orders these tests. They may be ordered for routine screening, monitoring a chronic condition, or evaluating symptoms like swelling or fatigue.

Preparation

Fasting is usually not required for kidney blood tests, but your clinician may ask you to fast if other tests are done at the same time. Tell your provider about all medications and supplements you take, as some can affect results.

Results and what they mean

Results are reported as numbers with reference ranges, and your clinician interprets them alongside your health history, symptoms, and other tests. A single abnormal value does not always mean kidney disease. This is general information, not medical advice; discuss your results with a qualified healthcare professional.

Requesting the Kidney Health Tests in California

Order online, choose a certified collection site in California, and review results through a secure portal. No referral is required, and orders are processed confidentially. With coastal metros, inland towns, and rural counties with very different access to testing, it pays to schedule your collection in advance.

Frequently asked questions

Do I need to fast for a kidney blood test?

Usually no. Fasting is only needed if your clinician orders other tests that require it.

Can I take my medications before the test?

Ask your clinician. Some medications and supplements can affect kidney test results, so follow their instructions.

How long does it take to get results?

Most kidney blood test results are available within 1 to 3 business days.

What if my results are abnormal?

Your clinician will review them with you and may repeat the test or order additional tests to understand the cause.

Kidney Health Tests by city in California

All testing in California → Full Kidney Health Tests guide →