How should Oral Rehydration Solution (ORS) be stored?

Proper Storage of Oral Rehydration Solution (ORS)

Oral rehydration solution (ORS) should be stored in a clean, sealed container at room temperature, and once prepared, should be used within 24 hours to maintain its effectiveness and prevent contamination.

Preparation and Storage Guidelines

Preparation of ORS

• ORS consists of 4 key ingredients that should be dissolved in 1 liter of clean drinking water 1:
  • Sodium chloride (3.5 grams)
  • Trisodium citrate dihydrate (2.9 grams) or sodium bicarbonate (2.5 grams)
  • Potassium chloride (1.5 grams)
  • Glucose (20.0 grams)

Storage of Prepared ORS

1. Container: Store in a clean, covered container to prevent contamination
2. Temperature: Keep at room temperature (not in direct sunlight or extreme heat)
3. Duration: Use within 24 hours after preparation
4. Discard: Throw away any unused solution after 24 hours

Storage of Pre-packaged ORS

• Powdered ORS packets:
  • Store in a cool, dry place
  • Keep packets sealed until ready to use
  • Check expiration dates before use
• Pre-mixed commercial ORS:
  • Store according to manufacturer's instructions
  • Maintain at recommended temperature (typically room temperature)
  • Observe expiration dates

Evidence-Based Considerations

Research shows that the osmolality of ORS products can be affected by storage conditions and time 2. Only one pre-mixed ORS product maintained compliance with WHO guidelines after prolonged storage at room temperature and elevated temperatures (31°C) for two months 2.

Five of six powdered ORS products tested were found to comply with WHO osmolality guidelines, showing minimal variation between packets of the same formulation 2. This suggests that powdered formulations may have better stability characteristics when stored properly.

Clinical Importance

Proper storage of ORS is critical because:

1. Effectiveness: Improperly stored ORS may lose its therapeutic properties
2. Safety: Contaminated solutions can cause additional illness
3. Mortality reduction: Correctly prepared and stored ORS can prevent up to 93% of diarrhea deaths 3

Common Pitfalls to Avoid

• Do not refrigerate prepared ORS as cold liquids may cause cramping
• Do not add additional ingredients (sugar, flavoring) that could alter the electrolyte balance
• Do not store in unclean containers which could introduce contaminants
• Do not use beyond 24 hours after preparation due to risk of bacterial growth
• Do not expose to extreme temperatures which may affect stability and efficacy

Special Considerations

For emergency settings or avulsed tooth storage, ORS has been shown to be an effective medium for preserving periodontal ligament cell viability 4. In these cases, the same storage principles apply, but the solution would be used for a different purpose than oral rehydration.