Can Oral Rehydration Solution (ORS) water be stored in the fridge?

Storing Oral Rehydration Solution (ORS) in the Refrigerator

Yes, Oral Rehydration Solution (ORS) can be safely stored in the refrigerator, which may help maintain its quality and prevent bacterial growth.

Safety of Refrigerated ORS

Refrigeration of ORS is a safe practice that can help maintain the solution's quality and prevent bacterial contamination. According to evidence, ORS can become contaminated when prepared with unboiled water and left at room temperature 1. This is particularly important since:

• 88% of water samples in one study were found to be unsatisfactory for drinking
• 35% of ORS prepared with unboiled water showed increased bacterial count after 24 hours at room temperature
• 57% of ORS prepared with unboiled water showed growth of coliform bacilli 1

Preparation and Storage Guidelines

Proper Preparation

1. Use clean drinking water to prepare ORS 2
2. Ideally, boil water for at least 5 minutes before preparing ORS to eliminate bacterial contamination 1
3. Follow standard ORS formulation:
   • Sodium chloride (3.5g)
   • Trisodium citrate dihydrate (2.9g) or sodium bicarbonate (2.5g)
   • Potassium chloride (1.5g)
   • Glucose (20g)
   • Dissolve in 1 liter of clean water 2

Storage Recommendations

• Refrigeration is advisable to maintain quality and prevent bacterial growth
• Properly prepared ORS can be stored for future use 3
• Pre-packaged ORS can remain stable for up to three months when properly stored 3

Clinical Considerations for ORS Use

Appropriate ORS Selection

• Use low-osmolarity ORS for all age groups and causes of diarrhea 4
• Commercial formulations that can be used include Pedialyte, CeraLyte, and Enfalac Lytren 4
• Avoid using apple juice, Gatorade, and commercial soft drinks as rehydration solutions 4

Administration Guidelines

• For mild to moderate dehydration, ORS should be given until clinical dehydration is corrected 4
• For infants <10kg: 60-120 ml ORS for each diarrheal stool or vomiting episode (up to ~500 ml/day)
• For children >10kg: 120-240 ml ORS for each diarrheal stool or vomiting episode (up to ~1 L/day)
• For adolescents and adults: Ad libitum, up to ~2 L/day 4

Special Considerations

• For patients with vomiting, administer small volumes (5-10 ml) every 1-2 minutes, gradually increasing the amount 4
• Continue replacement as long as diarrhea or vomiting persists 4
• If unable to drink, consider nasogastric tube administration or IV fluids 4

Pitfalls and Caveats

1. Contamination risk: ORS prepared with unboiled water can become contaminated. Always use clean, preferably boiled water 1.

2. Altering composition: Adding flavoring agents like fruit juices can significantly alter the electrolyte composition and osmolality of ORS, making it less effective for rehydration 5.

3. Expiration concerns: While refrigeration helps preserve ORS, it's still important to check for any changes in appearance, smell, or consistency before use 3.

4. Overhydration risk: In elderly patients with chronic heart or kidney failure, careful monitoring is needed to prevent overhydration when administering ORS 4.

5. Temperature considerations: Very cold ORS directly from the refrigerator may not be well tolerated, especially by young children. Consider allowing it to warm slightly before administration.

By following these guidelines, ORS can be safely stored in the refrigerator, helping to maintain its quality and effectiveness while preventing bacterial contamination.