Oral Sodium Chloride Tablets for Hyponatremia
The oral sodium chloride tablets used to treat mild hyponatremia are simply called "sodium chloride tablets" or "salt tablets"—there is no proprietary brand name required, as these are generic pharmaceutical-grade sodium chloride preparations.
Standard Formulation and Dosing
- Pharmaceutical-grade sodium chloride tablets are the standard oral formulation, with each 1 gram tablet containing approximately 17 mEq of sodium 1
- For mild to moderate hyponatremia requiring oral supplementation in conditions like SIADH refractory to fluid restriction, the typical dose is 100 mEq (approximately 6 grams) of sodium chloride three times daily, totaling about 7 grams of sodium per day 1
- In your patient's case with a sodium of 129 mEq/L, salt tablets would be used as an adjunct to fluid restriction (1-1.5 L/day) for euvolemic hyponatremia if SIADH is confirmed 1, 2
Clinical Application in Mild Hyponatremia
- Salt tablets have been shown to safely and effectively correct SIADH-related hyponatremia in elderly patients when used temporarily alongside fluid restriction, with resultant reduced length of hospital admission 2
- The hourly administration of oral sodium chloride tablets, calculated to deliver the equivalent of 0.5 mL/kg/h of 3% NaCl, can provide a graded and predictable increase in serum sodium concentration 3
- For a patient with sodium 129 mEq/L and multiple comorbidities, salt tablets offer a safer alternative to hypertonic saline while avoiding the risks of vaptans (such as overly rapid correction and increased thirst) 4
Important Prescribing Considerations
- Home preparation using table salt is NOT recommended due to potential errors in formulation—only pharmaceutical-grade tablets should be used 1
- Avoid potassium-containing salt substitutes, as patients with hyponatremia are at risk for hyperkalemia 1
- Monitor serum sodium every 24-48 hours initially when starting salt tablet therapy to ensure safe correction rates 1
- The maximum correction should not exceed 8 mmol/L in 24 hours to prevent osmotic demyelination syndrome 1, 5
Volume Status Assessment Required
- Before prescribing salt tablets, you must determine if your patient has euvolemic (SIADH), hypovolemic, or hypervolemic hyponatremia 5
- For hypervolemic hyponatremia (heart failure, cirrhosis), salt tablets would worsen fluid retention and are contraindicated—fluid restriction alone is appropriate 1
- For hypovolemic hyponatremia, isotonic saline infusion is preferred over oral salt tablets 5
- Salt tablets are most appropriate for euvolemic hyponatremia (SIADH) when fluid restriction alone has failed 1, 2
Common Pitfalls to Avoid
- Never use salt tablets as first-line therapy—fluid restriction to 1 L/day is the cornerstone of SIADH treatment, with salt tablets added only if no response 1
- Do not prescribe salt tablets without first confirming the volume status and underlying cause of hyponatremia 5
- Avoid using salt tablets in patients with heart failure or cirrhosis with hypervolemic hyponatremia, as this will exacerbate fluid overload 1