SODIUM

A sodium test, also known as a sodium blood test, measures the amount of sodium in your blood. Sodium is an electrolyte and mineral that helps your body maintain fluid and acid-base balance, and helps your muscles and nerves function properly.

Sodium test

Purpose

Detects abnormal sodium levels, monitors conditions that affect fluid and electrolyte balance, and monitors medications that affect sodium levels

Normal range

135–145 milliequivalents per liter (mEq/L)

When to get a test

If you've had a recent injury, surgery, or serious illness, or if you consume large or small amounts of salt or fluid

What it can show

Low sodium (hyponatremia) or high sodium (hypernatremia)

Symptoms of low sodium

Fatigue, nausea, vomiting, headache, loss of appetite, confusion, hallucinations, loss of consciousness, or coma

Symptoms of high sodium

Thirst, urinating very little, vomiting, diarrhea, confusion, muscle twitching, or seizures

The body needs about 3,400 milligrams of sodium per day, which can come from salt, fruits, vegetables, and dairy products.