What is the normal range for Sodium?

What is the normal range for Sodium?

• A. 140 mEq/L
• B. 125-135 mEq/L
• C. 135-145 mEq/L
• D. 150-160 mEq/L

Answer: (C)

Normal sodium in the blood is kept in a narrow window to maintain extracellular fluid balance and nerve function. The reference range for serum sodium is 135 to 145 mEq/L. Values within this span are considered normal, with 140 mEq/L being a typical level you might see. When sodium falls below 135, the result is hyponatremia, which can cause symptoms from confusion to seizures due to swelling of brain cells. When sodium rises above 145, hypernatremia occurs, leading to cellular dehydration, thirst, and confusion. This range is the best answer because it accurately defines the normal span used in clinical practice across labs and patient populations. Other options either fall outside this range or give a single value, which does not represent the full normal range.

Normal sodium in the blood is kept in a narrow window to maintain extracellular fluid balance and nerve function. The reference range for serum sodium is 135 to 145 mEq/L. Values within this span are considered normal, with 140 mEq/L being a typical level you might see. When sodium falls below 135, the result is hyponatremia, which can cause symptoms from confusion to seizures due to swelling of brain cells. When sodium rises above 145, hypernatremia occurs, leading to cellular dehydration, thirst, and confusion. This range is the best answer because it accurately defines the normal span used in clinical practice across labs and patient populations. Other options either fall outside this range or give a single value, which does not represent the full normal range.