When are sodium chloride tablets indicated for treating hyponatremia?

From the Guidelines

Sodium chloride tablets are generally not indicated for treating hyponatremia except in specific, limited circumstances, such as mild, chronic hyponatremia in euvolemic patients with normal renal function, where they may be used at doses of 1-2 grams three to four times daily 1.

Key Considerations

• The primary approach to treating hyponatremia involves addressing the underlying cause rather than simply providing salt supplementation.
• For acute or severe hyponatremia (sodium <120 mEq/L with neurological symptoms), intravenous hypertonic saline (3% NaCl) is the preferred treatment, not oral tablets, to rapidly correct serum sodium levels while minimizing the risk of osmotic demyelination syndrome 1.
• Treatment decisions should be based on the patient's volume status (hypovolemic, euvolemic, or hypervolemic), the severity of symptoms, and the chronicity of the condition.
• Oral salt tablets can increase sodium levels too slowly for urgent situations and may worsen conditions like heart failure or cirrhosis where sodium and fluid retention are problematic.

Management Strategies

• Mild hyponatremia (Na 126-135 mEq/L) in cirrhosis without symptoms may not require specific management apart from monitoring and water restriction 1.
• Water restriction to 1,000 mL/day and cessation of diuretics is recommended for moderate hyponatremia (120-125 mEq/L), with more severe restriction and albumin infusion considered for severe hyponatremia (<120 mEq/L) 1.
• The use of vasopressin receptor antagonists and hypertonic saline should be approached with caution, considering the risks and benefits, especially in patients with cirrhosis 1.

Correction Rate

• When correction of chronic hyponatremia is indicated, the goal rate of increase of serum sodium is 4-6 mEq/L per 24-hour period, not to exceed 8 mEq/L per 24-hour period to ameliorate the risk of osmotic demyelination syndrome 1.

From the Research

Indications for Sodium Chloride Tablets in Hyponatremia

Sodium chloride tablets are indicated for the treatment of hyponatremia in certain cases. The following are some of the indications:

• Mild and asymptomatic hyponatremia can be treated with adequate solute intake (salt and protein) and initial fluid restriction (FR) with adjustments based on serum sodium (sNa) levels 2
• Euvolemic hyponatremia can be treated with restricting free water consumption or using salt tablets or intravenous vaptans 3
• Hypervolemic hyponatremia is treated primarily by managing the underlying cause (e.g., heart failure, cirrhosis) and free water restriction, and salt tablets may be considered in some cases 3
• Hourly oral sodium chloride tablets can be used as an alternative to intravenous 3% NaCl for selected patients with severe hyponatremia, in conjunction with careful monitoring of the serum sodium concentration 4

Patient Selection

The decision to start sodium chloride tablets for hyponatremia should be based on the individual patient's condition, including:

• Severity of hyponatremia
• Presence of symptoms
• Underlying cause of hyponatremia
• Fluid volume status (hypovolemic, euvolemic, or hypervolemic)
• Ability to monitor serum sodium levels closely 2, 4, 3, 5

Monitoring and Adjustments

Close monitoring of serum sodium levels is crucial when using sodium chloride tablets to treat hyponatremia, and adjustments should be made as needed to avoid overly rapid correction or overcorrection 2, 4, 3, 5