What are examples of oral glucose saline solutions for managing dehydration?

Oral Glucose-Saline Solutions for Managing Dehydration

The most widely recommended oral glucose-saline solution is the modified WHO cholera rehydration solution (also called St. Mark's solution), which contains 60 mmol sodium chloride (3.5 g), 30 mmol sodium bicarbonate (2.5 g), and 110 mmol glucose (20 g) per liter of tap water. 1

Standard Formulations

Modified WHO Cholera Solution (St. Mark's Solution)

The gold standard for high-output stoma patients contains: 1

• Sodium chloride: 60 mmol (3.5 g)
• Sodium bicarbonate (or citrate): 30 mmol (2.5 g bicarbonate or 2.9 g citrate)
• Glucose: 110 mmol (20 g)
• Tap water: 1 liter

This formulation provides a total sodium concentration of 90 mmol/L, which matches the sodium concentration in jejunostomy fluid (approximately 100 mmol/L). 1, 2

Alternative High-Sodium Rehydration Solution

For patients requiring higher sodium replacement: 1

• Sodium chloride: 120 mmol (7 g)
• Glucose: 44 mmol (8 g)
• Tap water: 1 liter

This provides 120 mmol/L sodium and is useful when stomal losses exceed 3 liters per day. 1

WHO-ORS (Standard International Formula)

The World Health Organization's standard oral rehydration solution contains (per liter): 1

• Sodium: 90 mmol/L
• Potassium: 20 mmol/L
• Chloride: 80 mmol/L
• Base (bicarbonate or citrate): 30 mmol/L
• Glucose: 111 mmol/L (2%)
• Total osmolarity: 311 mOsm/L

This formulation was originally designed for cholera but has proven effective for all types of diarrheal dehydration regardless of etiology, age, or nutritional status. 1, 3

Commercial Preparations Available in the United States

For Maintenance and Mild Dehydration

Pedialyte and Ricelyte are the most commonly used commercial solutions in the U.S., containing: 1

• Pedialyte: 45 mEq/L sodium
• Ricelyte: 50 mEq/L sodium (contains rice-syrup solids instead of simple glucose)

These lower-sodium formulations (40-60 mEq/L) are designed for maintenance therapy and prevention of dehydration, particularly in viral diarrhea common in developed countries. 1 However, when using these for rehydration in high-output situations, additional low-sodium fluids (breast milk, formula, or water) must be provided to prevent sodium overload. 1

For Rehydration

Solutions containing 75-90 mEq/L sodium are preferable for active rehydration, especially when purging rates exceed 10 mL/kg/hour. 1 While Pedialyte and Ricelyte can be used for rehydration when the alternative is inappropriate fluids or IV therapy, higher sodium solutions are more physiologically appropriate. 1

Newer Formulations

Glucodrate®

A more palatable pre-packaged solution that maintains similar efficacy to the modified WHO cholera solution, with 89% of patients preferring it over the traditional formulation. 4 While it shows slightly lower net sodium absorption (difference of 11 mmol), this trade-off may be acceptable given improved palatability and compliance. 4

Rice-Based ORS

Contains cooked rice powder instead of glucose, providing complex carbohydrate polymers that are slowly digested without creating excessive osmotic load. 1 Rice-based formulations have shown reduced duration of diarrhea (by approximately 11 hours) compared to standard glucose-based solutions. 5

Critical Principles for Use

Sodium Concentration Requirements

The sodium concentration must be at least 90 mmol/L for patients with high-output jejunostomy or ileostomy because each liter of jejunostomy fluid contains approximately 100 mmol/L sodium. 1, 2, 6 Solutions with lower sodium concentrations will not adequately replace losses and will worsen dehydration. 1

Glucose-Sodium Coupling

Glucose enhances sodium absorption through coupled intestinal transport (sodium-glucose cotransport), which remains intact even during secretory diarrhea. 1, 6, 7 This physiologic mechanism is the foundation for all oral rehydration solutions. 7

Osmolarity Considerations

Hypotonic solutions (≤270 mOsm/L) are generally more effective than hypertonic solutions (≥310 mOsm/L) for non-cholera diarrhea, with optimal formulations containing 50-60 mmol/L sodium and 90-100 mmol/L glucose producing maximal water absorption. 7, 5 However, for cholera and high-output stomas, the higher sodium concentration (90 mmol/L) takes precedence despite slightly higher osmolarity. 1

Common Pitfalls to Avoid

Never encourage patients with high-output stomas to drink hypotonic fluids (water, tea, coffee, fruit juices) in large quantities, as this paradoxically increases stomal output and worsens sodium depletion. 1, 2, 6 Hypotonic oral fluids should be restricted to less than 500 mL daily. 1, 2

Avoid hypertonic fluids containing sorbitol or excessive glucose (fruit juices, Coca-Cola, most commercial sip feeds), as these cause osmotic water and sodium losses from the stoma. 1, 6

Do not use commercial sports drinks as oral rehydration solutions—they have insufficient sodium content and excessive sugar compared to proper ORS formulations. 6

High carbohydrate concentrations (>2.5% glucose) increase the risk of hypernatremia through osmotic effects, not the sodium content itself. 3, 8 Osmotic diarrhea from carbohydrate malabsorption is a more likely cause of hypernatremia than excessive dietary sodium. 8