Sodium Serum Test

Serum Sodium Test

It is a simple blood test that is used to find out sodium levels in your blood. Sodium is an electrolyte present in your body along with other electrolytes like potassium, chloride, and bicarbonate. These electrolytes play an important role in maintaining water and acid-base balance in the body. Any derangement in their levels may lead to serious consequences.

The various functions of sodium include keeping a check on water and electrolytes levels as well as the proper functioning of nerves and muscles in the body. Sodium also helps to maintain normal blood volume and blood pressure. The level of sodium is regulated by a hormone called aldosterone which is produced by adrenal glands in the body this hormone directs the kidney to excrete excess sodium in the urine and vice versa. Sodium is also excreted through skin in sweat and in the stool.

The main source of sodium in our body is food (in natural form), table salt (in form of sodium chloride), and baking soda (in form of sodium bicarbonate). Various medications also have sodium in them.

Why is the Serum Sodium Test prescribed?

Your healthcare provider may ask you to undergo this test in the following circumstances:

 

• Presence of symptoms suggesting low sodium levels like vomiting, dizziness, fatigue, loss of consciousness, etc
• Presence of kidney disease, liver disease, severe diarrhea, heart failure, Addison disease, hypothyroidism, Cushings syndrome, etc
• If on certain medications like diuretics, antidepressants, analgesics, corticosteroids, laxatives, etc
• Presence of symptoms suggesting high sodium levels like thirst, swelling of hands and feet, rapid heartbeat, loss of sleep, etc
• As a part of general health check-up in absence of any symptoms

What are the components of Serum Sodium Test?

The presence of low sodium levels is called HYPONATREMIA which can be due to kidney disease, liver disease, severe diarrhea, severe vomiting, heart failure, excessive sweating, etc

The presence of high sodium levels is called HYPERNATREMIA which can be due to Cushing’s syndrome, high level of aldosterone, excess salt intake, etc.

Procedure and Prerequisites

The sample for serum sodium is taken from blood by inserting a small needle into vein of your arm. A small amount of blood is then collected in the test tube or vial. You may feel little pain due to needle prick. You may resume your daily activities immediately. If you are on certain medications, you may have to stop them before the test after consultation with your doctor.

Reference Range

Normal range -136-145 mEq/L