Calcium, Serum or Plasma Concentration
This test measures the amount of calcium in your blood, either in serum or plasma. Calcium is an essential mineral that helps with muscle and nerve function, bone health, and blood clotting.
["Your calcium level helps doctors check for conditions like low or high calcium, which can affect many body systems."]
Key facts at a glance
- LOINC
- 77614-6
- Short code
- CALC10
- Synonyms
- Calcit 10M p chal SerPl-sCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top serum tube (no anticoagulant) or serum separator tube (SST)
- Units
- N/A
- Critical range
- — – 293 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 0–120 years
- Method
- Chemiluminescent Immunoassay (CLIA) or Electrochemiluminescence Immunoassay (ECLIA)
- CPT
- 82308
- SNOMED
- 39529005
- Specimen volume
- 1.0 mL serum (minimum 0.5 mL)
- Stability
- Serum stable for 8 hours at room temperature; 2 days at 2-8°C; frozen at -20°C for up to 30 days. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 50
- Lipemia max
- 100
- Icterus max
- 25
- TAT
- 4–24 hours
- Order
- routine
Why Is This Test Done?
Doctors may order this test if you have symptoms like muscle cramps, bone pain, or unusual fatigue. It’s also used to monitor conditions such as kidney disease, osteoporosis, or hyperparathyroidism, or to check for calcium-related disorders like hypocalcemia (low calcium) or hypercalcemia (high calcium).
What to Expect Before the Test
No special preparation is usually needed. You may be asked to fast for 8–12 hours before the test if it involves drawing blood from a vein, but this depends on your doctor’s instructions. If you’re taking calcium supplements, ask your doctor whether to stop them temporarily.
What Happens During the Test?
A healthcare provider will draw blood from a vein in your arm using a small needle. The blood sample is then sent to a lab for testing. The process takes a few minutes, and you may feel a brief pinch or slight discomfort.
What the Results Mean
Results are typically reported as a numerical value (e.g., in milligrams per deciliter, mg/dL). While reference ranges vary by lab, very low or very high levels may signal underlying health issues that need further evaluation.
Reference range
Post-stimulation calcitonin values are interpreted relative to baseline. A stimulated calcitonin level >100 pg/mL (29.3 pmol/L) in males or >50 pg/mL (14.6 pmol/L) in females is highly suggestive of medullary thyroid carcinoma (MTC). Peak stimulated values should be evaluated in clinical context with baseline and other diagnostic findings.N/A
No special preparation required; however, the stimulation test (typically with calcium gluconate or pentagastrin) must be conducted under medical supervision. Patient should remain recumbent during the procedure. Fasting is not required but may be recommended depending on institutional protocol.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Abnormal calcium levels can indicate serious conditions, such as thyroid disorders, kidney problems, or metabolic disorders. Low calcium may cause muscle spasms, seizures, or weakened bones, while high calcium can lead to nausea, confusion, or kidney stones. Your doctor will discuss results in the context of your overall health and symptoms.
Short name
Calcium Level
Frequently asked questions
How long does it take to get my calcium test results?
Can I eat or drink anything before my calcium test?
What should I do if my calcium level is too high or too low?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 10, 2026. · Read our editorial policy