BUN and Creatinine with Ratio
The two routine blood markers of kidney function, plus the ratio that flags dehydration versus kidney trouble.
Consider this test if:
- Setting a kidney-function baseline, especially with high blood pressure, diabetes, or a family history of kidney disease
- Taking medications cleared by or hard on the kidneys (NSAIDs, certain blood pressure drugs, contrast agents)
- Swelling, fatigue, or changes in how often or how much you urinate
- Training hard or eating high protein and watching hydration and kidney load
- Rechecking after a previously borderline or abnormal kidney result
- HSA/FSA eligible
- Results delivered to your dashboard · Reviewed by a real clinician
- Drawn at a CLIA/CAP-accredited lab near you ·
Pre-test considerations
No fasting is required. Heavy protein intake, dehydration, intense exercise, and creatine supplements can raise these values, so test under typical conditions rather than right after a hard workout or a very high-protein meal. Note any creatine supplementation, since it can elevate creatinine independent of kidney function.
Video consult with your Care Team
A 1:1 call to discuss your health.
What members say on Trustpilot
What this test is for
Creatinine is a waste product of normal muscle metabolism that the kidneys filter out, so a rising level signals that filtration is slowing. Blood urea nitrogen (BUN) measures urea, the nitrogen waste from protein breakdown, and it shifts with hydration, protein intake, and GI bleeding as well as kidney function. The BUN-to-creatinine ratio helps separate causes: a high ratio points toward dehydration or low blood flow to the kidneys, while both values rising together points more toward the kidneys themselves. Elevations are commonly investigated alongside high blood pressure, diabetes, swelling, fatigue, or changes in urination.
This pairing reports both values and their ratio. If you also want filtration translated into a single number, the Creatinine with eGFR and BUN/Creatinine Ratio Panel variants add the CKD-EPI estimated glomerular filtration rate.
Biomarkers tested
Includes 2 biomarkers
Creatinine is a waste product released as your muscles break down creatine for energy, and your kidneys filter it out of the blood at a steady rate. When creatinine rises, it usually means the kidneys are filtering less efficiently, making it the core marker for kidney function and the basis for calculating eGFR. Test it as a baseline for kidney health, to monitor the impact of blood pressure, diabetes, high-protein diets, or supplements like creatine, or to investigate unexplained fatigue, swelling, or changes in urination.
- Specimen
- Serum or plasma
- Measures
- Mass concentration
Blood urea nitrogen tracks the waste product your liver makes when it breaks down protein, cleared by kidneys that filter it out of circulation. High BUN points to reduced kidney filtration, dehydration, or a high protein intake, while low levels can reflect liver trouble or very low protein diets. Paired with creatinine, it rounds out a kidney function baseline and helps investigate fatigue, swelling, changes in urination, or unexplained shifts tied to diet, hydration, or medication changes.
- Specimen
- Serum or plasma
- Measures
- Mass concentration
What to expect
- 1 Book instantly
Click, book, done. Choose a convenient lab location near you. Transparent, up-front pricing.
- 2 Quick lab visit
Testing to fit your busy schedule, usually 15 minutes or less. Walk-in and appointments available.
- 3 Fast, dashboard-delivered results
Your results post straight to your dashboard as soon as the lab completes them.
- 4 Expert guidance
Included with Mito membership. A clinician reviews your results and your personalized action plan follows, with clear next steps.
Everything your health needs,
in one membership
-
Every test at our cost
Members pay our cost on every test, with lab fees passed straight through. The full receipt is itemized, never padded.
-
Continuous tracking, all in one place
Upload past labs and watch your trends over time. Every marker and visit lives in one longitudinal record, so all your care stays together.
-
Year-round clinician support
Text anytime and get clinician-reviewed answers. When you want to go deeper, 1:1 consultations are available at affordable rates.
All for $9/month
Order any test or consult without joining. For $9/month, members unlock member prices, trend tracking, and year-round clinician guidance.
Mito Membership
$9 /mo
cancel anytime
Without membership
$0
pay as you go
At-cost pricing on labs, scans, and more
Priority turnaround on your results
On-demand clinician consults when you need guidance
Personalized action plans across supplements, exercise, nutrition, and sleep
AI health coaching to help you act on your results
Year-round medical support, with in-chat clinician escalation
All your health records in one personal vault, with trends and biological age tracking
Early access to new diagnostics and product releases
More tests to consider
Loading essentials…
Frequently asked questions
View all FAQsHow does pricing work?
Every test shows the member price next to the standard non-member price, so you can see what membership saves you. The member price is our cost — covering the lab and what it takes to run the service — never a profit on the test itself; Mito makes its money on the $9 membership, not on marking up your tests. Membership is $9/mo, and you still pay the lab’s order fee. Prices are itemized before you pay, with no hidden fees.
Where do I get tested?
Choose a partner lab (Quest, Labcorp, or BioReference) at checkout. If your cart spans multiple tests, we consolidate the whole order onto a single lab so you only make one visit.
Is this eligible for HSA/FSA?
Yes. This test is HSA/FSA eligible, and you can pay with your HSA/FSA card at checkout.
When will I get my results?
Your results post to your dashboard once your lab completes them, then a clinician reviews them and your full analysis and personalized action plan (with clear next steps) follow. Turnaround varies by test: specialty assays and at-home kits take longer, and each test shows its expected turnaround before you buy.
Do I need a doctor’s order?
No. Mito provides the lab order for you, so you can book and get tested without a separate doctor visit.
Recently viewed
Loading essentials…