Calcium, Ionized
The bioavailable fraction of calcium, more accurate than total calcium when albumin is abnormal.
Consider this test if:
- Total calcium came back borderline or did not match your symptoms
- Working up suspected hyperparathyroidism or a parathyroid abnormality
- Low albumin, liver disease, or kidney disease that can skew total calcium
- Symptoms of calcium imbalance: numbness, tingling, muscle cramps, fatigue, or kidney stones
- Following a known calcium or parathyroid disorder over time
- HSA/FSA eligible
- Typical results in 1-2 days · Reviewed by a real clinician
- Drawn at a CLIA/CAP-accredited lab near you ·
Pre-test considerations
No fasting is generally required. The sample handling matters more than prep: the tube must stay sealed because exposure to air shifts pH and can make the ionized calcium unmeasurable, so this is drawn as a dedicated, unopened tube. A morning draw is standard.
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What this test is for
Ionized calcium is the free, biologically active calcium circulating in the blood, the fraction your nerves, muscles, and bones actually use. Most calcium in the blood is bound to albumin, so total calcium can read normal or abnormal simply because protein levels shifted; ionized calcium measures the active portion directly and cuts through that distortion. It is the more reliable number when total calcium does not fit the clinical picture, as in primary hyperparathyroidism, low albumin, kidney disease, or acid-base disturbances. Abnormal results connect to symptoms across several systems: high calcium with fatigue, excessive thirst, constipation, kidney stones, or bone pain, and low calcium with numbness, tingling, muscle cramps, or spasms.
This is the specialized form. Routine screening uses the total calcium test, which is fine for most people; ionized calcium is the right choice when albumin is off, when total calcium is borderline, or when a parathyroid or calcium-regulation question needs a direct answer.
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 Typical results in 1-2 days
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
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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.
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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.
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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
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Without membership
$0
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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
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All your health records in one personal vault, with trends and biological age tracking
Early access to new diagnostics and product releases
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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.
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.
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