Calcium in Serum (Total)
This test measures the amount of calcium, a mineral essential for many bodily functions, in your blood serum. Calcium helps with muscle and nerve function, bone health, and blood clotting.
["A calcium blood test helps check for conditions affecting bone health, nerve function, or mineral balance."]
Key facts at a glance
- LOINC
- 87871-0
- Short code
- CT Clavicle-L
- Synonyms
- CT Clavicle-L
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- ct
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why This Test Might Be Ordered
Your doctor may order this test if you have symptoms like muscle spasms, unusual fatigue, or bone pain. It’s also used to monitor conditions such as kidney disease, osteoporosis, or hyperparathyroidism. Sometimes, it’s part of routine check-ups or before certain treatments.
What to Expect Before the Test
You’ll typically have a small needle inserted into a vein (usually in your arm) to draw blood. No special preparation is needed, but avoid eating or drinking anything (except water) for 8–12 hours before the test if instructed by your doctor.
What the Results Mean
Results are compared to standard ranges, but your doctor will interpret them based on your health history and symptoms. Low or high calcium levels can signal underlying issues that need further evaluation.
Common Conditions Linked to Calcium Levels
Abnormal calcium levels can indicate conditions like hypoparathyroidism (low calcium), hyperparathyroidism (high calcium), kidney problems, or vitamin D deficiencies. Chronic conditions like cancer or certain medications can also affect calcium.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance: Calcium is vital for nerve signaling, muscle contraction, and bone mineralization. Low levels may cause weakness or spasms, while high levels can lead to kidney stones or heart issues. Regular monitoring helps manage conditions like osteoporosis or metabolic disorders.
Short name
Total Serum Calcium
Frequently asked questions
How often should I get this test?
What are the normal ranges for this test?
Can diet or supplements affect calcium test results?
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 16, 2026. · Read our editorial policy