What is the typical oral (po) dose of sodium chloride for treating hyponatremia in adults?

Oral Sodium Chloride Dosing for Hyponatremia in Adults

For adults with hyponatremia, the typical oral sodium chloride dose is 936 mg (4 mL of 23.4% solution) per serving, which can be adjusted based on the severity of hyponatremia and clinical response. 1

Dosing Based on Severity of Hyponatremia

Mild Hyponatremia (126-135 mEq/L)

• Generally requires only monitoring and water restriction
• No specific sodium chloride supplementation needed unless symptomatic 2

Moderate Hyponatremia (120-125 mEq/L)

• Water restriction to 1,000 mL/day
• Cessation of diuretics
• Oral sodium chloride supplementation may be considered 3

Severe Hyponatremia (<120 mEq/L)

• More strict water restriction
• Oral sodium chloride supplementation
• Consider albumin infusion in cirrhotic patients 3, 2

Administration Guidelines

1. Standard FDA-approved dosing:

   • Adults ages 9-50: 4 mL (936 mg) of 23.4% sodium chloride solution
   • Children under 9 and adults over 50: Physician consultation required 1

2. Calculation method for individualized dosing:

   • For treatment equivalent to IV 3% saline: Calculate dose to deliver 0.5 mL/kg/h of 3% NaCl equivalent 4
   • Target correction rate: 4-6 mEq/L per 24 hours, not exceeding 8 mEq/L in 24 hours 3

Monitoring and Safety Considerations

• Rate of correction: Avoid increasing serum sodium by more than 8 mEq/L in 24 hours to prevent osmotic demyelination syndrome 3, 2
• Monitoring frequency: Check serum sodium levels every 2-4 hours initially, then every 4-6 hours once stabilized
• Duration of treatment: Continue until serum sodium reaches 125-130 mEq/L, then reassess 5

Special Populations

• Cirrhotic patients: Use with caution as they are at higher risk for osmotic demyelination syndrome 3
• Hypervolemic hyponatremia: Oral sodium chloride may worsen fluid overload; fluid restriction is primary approach 3
• Hypovolemic hyponatremia: Address underlying volume depletion with isotonic saline before considering oral sodium chloride 3

Cautions and Contraindications

• Avoid rapid correction in chronic hyponatremia (>48 hours duration)
• Use with extreme caution in patients with heart failure, cirrhosis, or kidney disease
• Monitor for signs of fluid overload, especially in patients with compromised cardiac function

Alternative Approaches

For severely symptomatic patients (seizures, coma), IV hypertonic saline (3%) should be used instead of oral supplementation, with a target initial correction of 4-6 mEq/L in the first 1-2 hours 6, 7.

Home preparation of sodium chloride supplements using table salt is not recommended due to potential errors in formulation that could result in dangerous hypo- or hypernatremia 3.