Renal Function Panel
Tracks kidney filtration, electrolytes, and mineral balance in one blood draw.
Consider this test if:
- High blood pressure, diabetes, or heart disease, where kidney monitoring is part of routine care
- A family history of kidney disease and you want a filtration baseline
- Tracking kidney function while on medications that affect the kidneys or electrolytes
- Swelling, changes in urination, fatigue, or unexplained nausea being investigated
- Following up an abnormal creatinine or eGFR to confirm the trend
- HSA/FSA eligible
- Typical results in 1 day · Reviewed by a real clinician
- Drawn at a CLIA/CAP-accredited lab near you ·
Pre-test considerations
Fasting overnight is preferred (12 hours, with 8 hours acceptable) because the panel includes glucose. Stay well hydrated, since dehydration can transiently raise BUN and creatinine. Heavy protein intake or intense exercise shortly before the draw can also nudge these values.
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What this test is for
The renal function panel is a serum blood test that checks how well your kidneys filter and regulate the body. It measures creatinine and calculated eGFR (the core estimate of filtration rate), BUN and the BUN/creatinine ratio, electrolytes (sodium, potassium, chloride, bicarbonate), glucose, and the minerals the kidneys help control: calcium, phosphorus, and albumin. Rising creatinine and BUN with a falling eGFR point to reduced kidney function, while shifts in potassium, bicarbonate, calcium, or phosphorus often appear as kidney disease progresses. It is most useful for people with high blood pressure, diabetes, heart disease, or a family history of kidney disease, since early kidney decline is usually silent and shows up in these numbers before symptoms do.
This is the serum-only view of kidney function. It is broader than the Basic Metabolic Panel because it adds phosphorus and albumin, and it differs from the Kidney Panel, which adds a urine albumin-creatinine ratio to catch early protein leakage the blood cannot show.
Biomarkers tested
Includes 12 biomarkers
Albumin is the protein your liver churns out in the largest quantity, and it does double duty: it holds water inside your blood vessels (so fluid doesn't leak into tissue) and ferries hormones, fatty acids, and medications through your bloodstream. Low albumin points to liver disease, kidney protein loss, chronic inflammation, or poor nutrition, and often shows up alongside swelling, fatigue, or unexplained weight loss. Because it reflects both liver production and overall protein status, it's a useful baseline check and a quick way to see whether inflammation or malnutrition is quietly dragging your protein reserves down.
- Specimen
- Serum or plasma
- Measures
- Mass concentration
This ratio compares urea nitrogen, a waste product the liver makes from protein breakdown, to creatinine, a byproduct of muscle metabolism, giving context that either marker alone can't. A high ratio points toward dehydration, high protein intake, or reduced blood flow to the kidneys, while a low ratio suggests liver trouble or a low-protein diet, so it's most useful for interpreting an abnormal BUN or creatinine rather than standing alone. Order it alongside kidney function testing when you're investigating fatigue, unexplained swelling, or changes in urination, or when you want to rule out dehydration as the cause of an odd creatinine result.
- Specimen
- Serum or plasma
- Measures
- Ratio
Calcium does far more than build bone: nerves fire, muscles contract, blood clots, and hormones release only when calcium levels stay in a tight range. This test measures total calcium in serum, which parathyroid hormone and vitamin D regulate together with your bones acting as the reserve tank. High calcium points to overactive parathyroid glands, excess vitamin D, or certain cancers, while low calcium suggests parathyroid or kidney dysfunction, vitamin D deficiency, or poor absorption, and either extreme can drive fatigue, muscle cramps, tingling, brain fog, or irregular heartbeat worth investigating.
- Specimen
- Serum or plasma
- Measures
- Mass concentration
Total CO2 measures the bicarbonate-based buffer your blood uses to keep pH stable, reflecting how your lungs and kidneys balance acid and base. Low levels point toward metabolic acidosis (from kidney disease, uncontrolled diabetes, or chronic diarrhea) while high levels suggest metabolic alkalosis or a compensated respiratory condition, both worth clarifying if you're dealing with unexplained fatigue, rapid breathing, or confusion. It's part of the standard electrolyte panel, so most people track it as a baseline metabolic marker alongside sodium, potassium, and chloride rather than ordering it alone.
- Specimen
- Serum or plasma
- Measures
- Substance concentration
Chloride is the main negative ion in your blood, working alongside sodium and bicarbonate to hold fluid balance, blood volume, and acid-base status steady. Low levels track with vomiting, dehydration, or metabolic alkalosis, while high levels point toward dehydration or metabolic acidosis, often from kidney or GI losses. Ordered as part of a basic metabolic panel, it mainly serves as a baseline check and a way to make sense of symptoms like dizziness, muscle cramps, or persistent fatigue tied to fluid or electrolyte shifts.
- Specimen
- Serum or plasma
- Measures
- Substance concentration
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
- Specimen
- Serum, plasma, or blood
- Method
- Creatinine-based (CKD-EPI)
- Measures
- Ratio
Glucose measures the sugar circulating in your blood right now, the fuel your cells burn for energy and the hormone insulin works constantly to keep in range. High readings point toward insulin resistance, prediabetes, or diabetes, while low readings can explain shakiness, lightheadedness, irritability, or brain fog between meals. Pair it with fasting insulin or A1c to see whether your body is managing glucose efficiently or working overtime to do it, and use it to track how diet, training, or sleep changes are actually moving your metabolism.
- Specimen
- Serum or plasma
- Measures
- Mass concentration
Phosphate works alongside calcium to build bone and teeth, and inside cells it powers ATP, the molecule that stores and releases energy for nearly everything you do. Low levels can drive muscle weakness, fatigue, and bone pain, and show up with poor nutrition, alcohol use, or refeeding after fasting, while high levels usually point to reduced kidney clearance or parathyroid and vitamin D imbalance. It's typically run alongside calcium, PTH, and kidney markers to sort out bone, kidney, or mineral metabolism issues, and it's a useful baseline for anyone tracking bone health or energy metabolism over time.
- Specimen
- Serum or plasma
- Measures
- Mass concentration
Potassium regulates the electrical signaling that fires your heart muscle, contracts your muscles, and controls nerve conduction, with cells and kidneys working together to keep it in a tight range. Levels that drift high or low show up as muscle weakness, cramping, palpitations, or fatigue, and can result from dehydration, kidney function changes, certain blood pressure medications, or heavy sweating from training. It's a core piece of any electrolyte or kidney panel, useful for a baseline check and essential context if you're on diuretics, ACE inhibitors, or pushing hard in endurance training where fluid and mineral losses run high.
- Specimen
- Serum or plasma
- Measures
- Substance concentration
Sodium is the main electrolyte outside your cells and it controls how water distributes across your body, keeping blood volume and blood pressure stable while nerves and muscles fire correctly. Low sodium shows up as fatigue, headache, confusion, nausea, or muscle cramps, and points to excess water retention, heavy sweating, certain medications, or kidney and hormone issues, while high sodium usually signals dehydration. It's a core part of any metabolic panel, useful as a baseline check and essential for investigating unexplained fatigue, dizziness, or muscle cramping, especially in endurance athletes or anyone on diuretics.
- Specimen
- Serum or plasma
- Measures
- Substance 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
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- 2 Quick lab visit
Testing to fit your busy schedule, usually 15 minutes or less. Walk-in and appointments available.
- 3 Typical results in 1 day
Your results post straight to your dashboard as soon as the lab completes them.
- 4 Expert guidance
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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.
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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.
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