Calcium (Serum) with Electrolyte Profile
This test measures your blood levels of calcium and other key electrolytes, which help regulate important bodily functions like muscle and nerve activity.
["Check your calcium and electrolyte balance to prevent serious health risks like muscle spasms or irregular heart rhythms."]
Key facts at a glance
- LOINC
- 21642-4
- Short code
- CACNA1S R1239G
- Synonyms
- CACNA1S p.R1239G Bld/T Ql
- Category
- chemistry
- Sample
- whole-blood
- Container
- EDTA (lavender-top) tube for whole blood; sterile container for tissue specimens
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- molgen
- CPT
- 81401
- SNOMED
- 53034-3
- Specimen volume
- 5-10 mL whole blood in EDTA tube; or 5-10 mg tissue in sterile container
- Stability
- Whole blood: Room temperature for 24 hours, refrigerated (2-8°C) for 7 days, frozen (-20°C) for long-term storage. Tissue: frozen (-20°C or lower) preferred; refrigerated acceptable for short term.
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 168–720 hours
- Order
- routine
What Does This Test Measure?
Your blood sample will be analyzed for calcium levels and additional electrolytes, including sodium, potassium, and chloride. These minerals play vital roles in maintaining fluid balance, nerve function, and muscle contractions. The test may also include magnesium and phosphate depending on the lab’s specific panel.
Why Might You Need This Test?
Doctors order this test when you have symptoms like muscle weakness, fatigue, confusion, or frequent urination. It’s also used to monitor conditions such as kidney disease, heart problems, or metabolic disorders that affect electrolyte levels.
Common Reasons for Testing
Common reasons include diagnosing or managing conditions like hypocalcemia (low calcium), hypercalcemia (high calcium), or electrolyte imbalances. It may also be part of routine check-ups for patients with chronic illnesses or those on certain medications that affect electrolytes.
What to Expect Before the Test
No special preparation is needed, but you may be asked to fast for 8–12 hours before the test if it involves a fasting sample. Wear comfortable clothing and arrive with your doctor’s instructions if you’re on medications.
Reference range
Negative (absence of CACNA1S p.Arg1239Gly pathogenic variant). Results reported as Detected/Not Detected.N/A
No fasting required. Patient should be informed that this is a genetic test and appropriate genetic counseling is recommended. A signed informed consent for genetic testing may be required.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Short name
Calcium and Electrolytes Panel
Frequently asked questions
How long will results take to come back?
What are the normal ranges for these tests?
Can I eat or drink before this 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 16, 2026. · Read our editorial policy