Sodium, Serum

The sodium blood test measures the amount of sodium in the blood.
Other names: Sodium test, Na test
The sodium test is part of the electrolyte panel or the basic metabolic panel and is tested along with other electrolytes like bicarbonates, chlorides, potassium etc. High levels of sodium can increase blood pressure and is important to maintain optimal levels. Sodium is absorbed in the body from the food we eat and drink and is excreted through urine, stool or sweat. Sodium is important for nerve and muscle function.

Who should get tested for Sodium?

Sodium testing is ordered when a person displays symptoms of low sodium like weakness, fatigue, dehydration, confusion and lethargy etc.

Sodium tests form an important part of electrolyte panel and is routinely ordered for monitoring treatment of specific conditions like high blood pressure, heart failure and to monitor liver and kidney diseases.

Why Sodium test?

• It is used to diagnose hyponatremia (low sodium) or hypernatremia (high sodium)
• Helps evaluate acid base imbalances (acidosis or alkalosis)
• Monitor medication of diuretics
• As part of routine screening in metabolic panel or electrolytes panel

Reference values for Sodium test: 136 - 145 mmol/L

Interpretation of Sodium Serum

There are certain conditions that lead to hyponatremia or low sodium and these include diarrhoea, vomiting, excessive sweating etc. Use of diuretics, kidney disease, liver disease, hypopituitarism and Addison’s disease can also cause low levels of sodium in the blood. Cushing Syndrome, Diabetes insipidus often lead to higher sodium levels in the blood.