Calcium in Serum or Plasma (Mass Concentration)
This test measures the amount of calcium, a mineral essential for many bodily functions, in your blood.
["Your blood calcium level helps doctors assess bone health, nerve function, and other vital processes."]
Key facts at a glance
- LOINC
- 75709-6
- Short code
- CALCFNA
- Synonyms
- Calcit LN FNA-mCnc
- Category
- chemistry
- Sample
- serum
- Container
- Sterile screw-cap vial or red-top vacuum tube for FNA washout fluid collection
- Units
- N/A
- Ref low
- 0
- Ref high
- 10
- Critical range
- — – 1000 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- ≥ 18 years
- Method
- Immunoassay (Chemiluminescent)
- CPT
- 82308
- SNOMED
- 39579002
- Specimen volume
- 0.5-1 mL of FNA washout fluid in sterile container; alternatively 1 mL serum
- Stability
- Refrigerated (2-8°C): 24 hours; Frozen (-20°C or below): 3 months. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 50
- Lipemia max
- 100
- Icterus max
- 25
- TAT
- 24–72 hours
- Order
- routine
Why Is This Test Done?
Doctors may order a calcium test to check for conditions like low or high calcium levels, which can cause symptoms such as muscle cramps, weakness, or irregular heartbeats. It’s also used to monitor bone diseases, kidney function, or metabolic disorders.
What to Expect Before the Test
No special preparation is usually needed, but you may be asked to fast for 8–12 hours before the test if it involves drawing blood. Stay hydrated unless instructed otherwise.
What Happens During the Test?
A healthcare provider will draw blood from a vein in your arm. You may feel a slight pinch, but the process is quick and painless. The sample is then sent to a lab for analysis.
What the Results Mean
Results are compared to standard ranges, but exact values can vary by lab. Abnormal results may trigger further testing or follow-up to identify causes like vitamin D deficiency, kidney disease, or thyroid issues.
Reference range
Reference range not established for fine needle aspirate specimens; results should be interpreted in conjunction with cytology and clinical context. Serum calcitonin reference: <10 pg/mL (males), <5 pg/mL (females).N/A
No special preparation required for the FNA procedure. If serum calcitonin is also ordered, fasting is not mandatory but a fasting sample is preferred for consistency.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance: Low or High Calcium Levels Can Cause Serious Health Risks
Short name
Calcium Level
Frequently asked questions
How Often Should I Get This Test?
What Are Common Causes of Abnormal Results?
Can I Adjust My Diet Before the Test?
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 15, 2026. · Read our editorial policy