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Sodium

Also known as Serum sodium test

You need to provide

Blood

This test is for

Male, Female

Test Preparation

No special preparation is required.

Understanding Sodium

What is Sodium?

A Sodium test is used to measure the amount of sodium, an electrolyte, in your body. This test is performed to evaluate your overall health and as a follow-up to ongoing conditions like high blood pressure. It is often done as part of routine health checkups.

Sodium is an important electrolyte present in all body fluids. It performs functions like controlling the amount of fluid in your body and balancing the body's pH level. It also helps your nerves and muscles to work properly. Therefore, an optimal amount of sodium is essential for regular body functioning. Deviation in sodium levels can cause hypernatremia (high amount of sodium) or hyponatremia (low amount of sodium), which may need a doctor’s attention.

Your doctor may advise a Sodium test if you experience symptoms such as weakness, fatigue, excessive thirst, decrease in the frequency of urination, muscle spasm and cramps, irritability, confusion, and seizures. This test may be used to investigate the cause of dehydration and generalized body swelling. It can also be advised if your blood pressure is not well-controlled. Usually, no special preparation is required for a Sodium test; eat and drink as per your daily routine.

Test result ranges are approximate and may differ slightly between different labs depending on the methodology and laboratory guidelines. Talk to your doctor about your specific test results. Narrate your complete medical history to help the doctor correlate your clinical and laboratory findings. The test results will help them determine your medical condition, make recommendations for lifestyle modifications such as diet and exercise, decide whether or not medication will be required to manage your health, and formulate your overall treatment plan.

What is Sodium used for?

A Sodium test is done:

As part of routine health checkups.
To check the water-electrolyte balance and acid-base (pH) balance of your body.
To detect the cause and monitor the treatment of dehydration or excess fluid buildup (edema).
To monitor the progress of the condition and treatment response while undergoing treatment for high blood pressure and diseases related to the kidneys, heart, liver, or adrenal gland.
To monitor patients who are receiving diuretic therapy, intravenous fluids, or dialysis.
To check the effects of medications that can affect your sodium levels, such as diuretics, birth control pills, antidepressants, and opioids.

What does Sodium measure?

A Sodium test is used to measure the amount of sodium in your body. Sodium is present in all body fluids and is found in the highest concentration in the extracellular fluid. The body absorbs the required amount of sodium through dietary salts and the remaining is eliminated through the kidneys. The body keeps your blood sodium within a normal and steady range by following three mechanisms:

By producing hormones that control the elimination of sodium through urine, such as natriuretic peptides and aldosterone.
By producing hormones that prevent water loss, such as antidiuretic hormone (ADH) or vasopressin.
By controlling thirst (an increase in blood sodium level can make you thirsty and cause you to drink water, returning your sodium to normal).

These mechanisms regulate the amount of water and sodium in the body and control blood pressure by keeping the amount of water in check. When the level of sodium in the blood changes, the water content in your body changes. These changes can be associated with dehydration, edema, and change in blood pressure.

Interpreting Sodium results

Interpretations

Normal range: 135 to 145 mmol/L

Hyponatremia: Below 135 mmol/L

Hypernatremia: Above 145 mmol/L

Sodium concentration in the body is maintained within a narrow normal range between 135 mmol/L and 145 mmol/L.

Hyponatremia or low blood sodium is indicated if sodium concentration lies below the normal range.

Hypernatremia or high blood sodium is indicated if sodium concentration lies above the normal range.

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

Frequently Asked Questions about Sodium

Q. Why do I need a sodium blood test?

Your doctor may suggest a sodium blood test if you show symptoms such as excessive thirst, decrease in the frequency of urination, muscle spasms and cramps, irritability, confusion, and seizures.

Q. What is hypernatremia and its associated symptoms?

Hypernatremia is a condition in which sodium levels in the blood rise higher than the normal range. Its symptoms include excessive thirst, less urination, diarrhea, confusion, restlessness, muscle weakness, irritability, and unconsciousness.

Q. What is hyponatremia and its associated symptoms?

Hyponatremia is a condition in which sodium levels in the blood fall lower than the normal range. Its symptoms include nausea, vomiting, headache, drowsiness, restlessness, irritability, muscle spasm or cramps, seizures, and coma.

Q. What are the causes of low sodium levels?

A low sodium level can have many causes, including consumption of too much water; kidney failure; heart failure; cirrhosis; use of diuretics, painkillers, or antidepressants; and hormonal changes.

Q. Can an increase in salt intake raise my sodium levels?

Yes, increasing salt intake can raise your sodium levels and too much salt in the diet can lead to high blood pressure, heart disease, and stroke.

Q. What other tests can be prescribed by the doctor in case the results of a sodium blood test are not normal?

Other tests that may be prescribed when blood sodium levels are not normal include a urine sodium test, electrolytes test, kidney function test, liver function test, blood phosphate test, or electrocardiogram (ECG).

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