Normal serum sodium range for adults?

Normal serum sodium range for adults?

• A. 120-130 mEq/L
• B. 150-160 mEq/L
• C. 135-145 mEq/L
• D. 140-150 mEq/L

Answer: (C)

Normal serum sodium in adults is about 135 to 145 mEq/L. This range reflects the balance of extracellular fluid and is essential for maintaining proper fluid distribution, nerve signaling, and muscle function. Values below 135 indicate hyponatremia, which can cause confusion, seizures, and fatigue, while values above 145 indicate hypernatremia, leading to dehydration and neurologic symptoms. The other ranges either sit clearly below the normal lower limit or above the normal upper limit, so they don’t represent the standard reference interval.

Normal serum sodium in adults is about 135 to 145 mEq/L. This range reflects the balance of extracellular fluid and is essential for maintaining proper fluid distribution, nerve signaling, and muscle function. Values below 135 indicate hyponatremia, which can cause confusion, seizures, and fatigue, while values above 145 indicate hypernatremia, leading to dehydration and neurologic symptoms. The other ranges either sit clearly below the normal lower limit or above the normal upper limit, so they don’t represent the standard reference interval.