Sodium Content in Normal Saline (0.9% NaCl)
One liter of intravenous normal saline (0.9% sodium chloride) contains 154 mEq (or 154 mmol) of sodium.
Composition Details
Normal saline (0.9% NaCl) contains 0.9 grams of sodium chloride per 100 mL, which translates to 9 grams of sodium chloride per liter 1
This solution provides 154 mEq/L of sodium and 154 mEq/L of chloride, making it a supraphysiologic chloride concentration compared to plasma 2
The sodium content can also be expressed as 3,542 mg of sodium per liter (since 154 mEq × 23 mg/mEq = 3,542 mg)
Clinical Context and Limitations
Large volume administration of 0.9% saline should be avoided due to its association with hyperchloremic metabolic acidosis, increased mortality, and major adverse kidney events 3, 4. The excess chloride concentration relative to plasma causes renal vasoconstriction and acute kidney injury 2.
Key Clinical Considerations:
If normal saline must be used, limit administration to a maximum of 1-1.5 liters to minimize chloride load and prevent complications 3, 1
Balanced crystalloid solutions (such as Ringer's Lactate or Plasmalyte) are strongly recommended as first-line fluid therapy in most clinical scenarios, as they reduce mortality and adverse renal events while maintaining better acid-base balance 3, 4
The routine use of 0.9% saline lacks convincing scientific basis and may be based on historical fallacy, as it is neither "normal" nor "physiological" in composition 5