Serum Calcium (Substance Concentration) – Quantitative

This test is done to help your doctor check how well your body is working, look for signs of illness, and guide decisions about your ongoing care and treatment.

Your healthcare provider may order this test to check for conditions affecting calcium balance, such as low or high calcium levels (hypocalcemia or hypercalcemia), kidney disease, bone disorders, or metabolic issues like hyperparathyroidism. It may also be part of routine screening or monitoring for certain medical conditions.

Before the test, your care team will explain the steps and tell you how to prepare, which may include avoiding certain foods, drinks, or medicines for a short time.

No special preparation is usually needed. You may be asked to fast for 8–12 hours before the test if it’s part of a broader metabolic evaluation. Bring any medications you’re currently taking, as some (like calcium supplements or certain diuretics) can affect results.

During the test, a trained member of your care team will perform the procedure in a comfortable setting, explain each step as it happens, and answer any questions you have.

A healthcare professional will draw blood from a vein in your arm using a small needle. You may feel a slight pinch, but the procedure is quick. The blood sample is then sent to a lab for analysis.

Possible results may show that everything looks normal, or they may point to a condition that needs closer attention, further testing, or treatment, which your doctor will explain.

Results are typically reported in milligrams per deciliter (mg/dL) or millimoles per liter (mmol/L). While reference ranges vary by lab, low or high values may signal underlying health concerns that need further investigation.