Test Detail
Understanding the Test
Test Measures
Interpreting Results
City Price Info
Other Tests
Content created by
Written by
Dr. Betina Chandolia
BDS, MDS - Oral Pathology and Microbiology
Reviewed by
Dr. Ashish Ranjan
MBBS, MD (Pharmacology)
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Serum Calcium

Also known as Calcium blood test, S. Calcium, Serum Ca
You need to provide
This test is for
Male, Female
Test Preparation
  1. Overnight fasting is preferred.

Understanding Serum Calcium

What is Serum Calcium?

A Serum Calcium test measures the level of calcium in the blood. This test detects various health problems associated with the bones, teeth, heart, kidneys, and hormonal imbalances like thyroid disorders or nerve diseases. It is often done as part of routine health checkups.

Calcium is one of the important and abundant minerals in our body. It performs various body functions, such as helping the nerves work properly, cell signaling, and muscle contraction. The body also needs calcium to keep the bones healthy and strong, for blood clotting, and to regulate heart rhythms.

A Serum Calcium test is performed if you experience symptoms such as weakness, fatigue, excessive urination and thirst, nausea, stomach pain, constipation, irregular heartbeat, brittle nails, weak and brittle bones, muscle cramps, irritability, or confusion. This test may also help check the treatment response for abnormal calcium levels and monitor critically ill patients suffering from cancer or kidney disorders. Usually, overnight fasting (8-12 hours) is preferred for this test. Do not eat or drink anything except water before the test. 

Test result ranges are approximate and may differ slightly between labs depending on the methodology and laboratory guidelines. Talk to your doctor about your specific test results. Narrate your complete medical history to help them correlate your clinical and laboratory findings and formulate an overall treatment plan.

What is Serum Calcium used for?

A Serum Calcium test is done:

  • As part of routine health checkups.
  • If you have symptoms of abnormal calcium levels, such as excessive urination and thirst, constipation, irregular heartbeat, brittle nails, weak and brittle bones, muscle cramps, irritability, or confusion.
  • To diagnose diseases that may cause calcium abnormalities, such as thyroid and parathyroid disorders, heart diseases, kidney diseases, bone disorders, and dental diseases and disorders that affect how your intestines absorb nutrients like calcium.
  • To assess the effectiveness of treatments like calcium and vitamin D supplements in the body.
  • To monitor the progress of treatment in conditions associated with the kidneys, heart, bones, thyroid, teeth, and also in certain types of cancers that may affect calcium levels in the body.
  • To monitor calcium levels in people during and after blood transfusions or intravenous fluids, in those undergoing major surgery, and in those who have blood protein abnormalities like low albumin.

What does Serum Calcium measure?

A Serum Calcium test measures the levels of calcium in the body. Calcium is the most abundant mineral in the body, and the majority of it is present in the bones and teeth, and the remaining portion (around 1%) is found in the blood. It is normally present in two forms in blood in about equal amounts, namely "bound calcium", which is attached to proteins in the blood, and "free calcium or ionized calcium", which is not attached to any protein. 

A Serum Calcium test cannot be used to check for a lack of calcium in your diet or osteoporosis (loss of calcium from bones) as the body can have normal calcium levels even in case of dietary deficiency of calcium. Moreover, the body can normalize mild calcium deficiency by releasing the calcium stored in bones.

Interpreting Serum Calcium results


Normal range: 8.5 to 10.5 mg/dL (2.2 to 2.7 mmol/L approx.)

Hypocalcemia: Below 8.5 mg/dL (Below 2.2 mmol/L approx.)

Hypercalcemia: Above 10.5 mg/dL (Above 2.7 mmol/L approx.)

Calcium concentration in the body is maintained within a narrow normal range between 8.5mg/dL and 10.5mg/dL.

Hypocalcemia or low blood calcium is indicated if calcium concentration lies below the normal range.

Hypercalcemia or high blood calcium is indicated if calcium concentration lies above the normal range.

Answers to Patient Concerns & Frequently Asked Questions (FAQs) about Serum Calcium

Frequently Asked Questions about Serum Calcium

Q. Are there any risks associated with the Serum Calcium test?

There is usually no risk associated with this test. However, some people may feel a slight sting while the needle is pricked and may experience some bleeding that is normal and usually not bothersome. Some people may experience slight swelling or bruising at the site of the needle prick. Applying ice 3-4 times daily for about a week may help reduce swelling and bruising. If it does not get better, consult your doctor.

Q. What are the signs that indicate you are not getting enough calcium in the body?

Brittle nails, tooth troubles, sleep problems, numbness and tingling in hands and feet, and muscle cramps are some of the signs that you are not getting enough calcium.

Q. Should I take calcium supplements if my test results show low calcium levels?

Always consult your doctor before taking calcium supplements. However, a healthy diet including milk, cheese, yogurt, green leafy vegetables, and almonds can support your daily calcium needs.

Q. What is hypocalcemia and its associated symptoms?

Hypocalcemia is a condition where the blood calcium levels are below the normal range. Symptoms associated with hypocalcemia include weak and brittle hairs, brittle nails, thin and brittle bones that fracture easily, numbness and tingling sensation, muscle spasms and cramps, confusion, memory loss, hallucinations, and seizures.

Q. What is hypercalcemia and its associated symptoms?

Hypercalcemia is a condition where blood calcium levels are higher than the normal range. The symptoms associated with hypercalcemia include headache, weakness, fatigue, excessive urination and thirst, nausea, stomach pain, constipation, irregular heartbeat, weak and brittle bones, muscle cramps, irritability, confusion, and coma, which can be potentially fatal.

Q. What is osteoporosis, and how is it related to calcium deficiency?

Bones are the primary reservoirs of calcium in our body. The body needs a constant level of calcium for the functioning of various parts, such as the heart, muscles, and nerves. When these body parts need calcium, they take it from the calcium stored in the bones. Over time, when the body depletes calcium stores in the bones, it leads to osteoporosis, characterized by fragile bones and an increased risk of falling.

Q. What other tests can be performed if my test results are abnormal?

Other tests that may be performed if your test results are abnormal include an ionized calcium test, urine calcium test, vitamin D test, electrolyte panel test, kidney function test, parathyroid hormone (PTH) test, PTH-related peptide test (PTHrH), and electrocardiography (ECG).

Q. When can false results appear in the Calcium Test?

False results may appear in newborns, showing hypocalcemia. This is usually due to the immature parathyroid gland. False results may also appear after a large volume of blood transfusion. Additionally, some medications can elevate or lower blood calcium levels.
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Serum Calcium test price for other cities

Price inBangaloreRs. 199
Price inKolkataRs. 199
Price inMumbaiRs. 199
Price inHyderabadRs. 199
Price inPuneRs. 199
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