Can bacteriostatic water be stored at room temperature for reuse another day?

Bacteriostatic Water Storage and Reuse

Bacteriostatic water should not be stored at room temperature for reuse on another day. It should be refrigerated if stored after opening and discarded after 28 days maximum. 1

Storage Requirements for Bacteriostatic Water

Temperature Considerations

• Room temperature storage: Not recommended for opened bacteriostatic water

  • Studies show significant bacterial growth can occur in water stored at room temperature (37°C) with counts increasing to 38,000 colonies/mL over 48 hours 2
  • Room temperature storage promotes microbial proliferation despite the bacteriostatic agent

• Refrigerated storage: Required for opened bacteriostatic water

  • Refrigeration (4°C) significantly reduces bacterial growth by 50% at 24 hours and 84% at 48 hours compared to room temperature 2
  • The CDC and Healthcare Infection Control Practices Advisory Committee recommend proper storage of sterile and bacteriostatic water to prevent contamination 1

Time Limitations

• Maximum storage time after opening: 28 days when refrigerated
• Discard any opened bacteriostatic water after this period regardless of appearance

Proper Handling Practices

Opening and Use

• Use aseptic technique when handling bacteriostatic water
• Clean the rubber stopper with alcohol before each entry
• Use sterile needles/syringes for each withdrawal
• Close immediately after use

Container Considerations

• Keep bacteriostatic water in its original container
• Do not transfer to secondary containers
• Ensure the container is properly sealed after each use
• Label with the date of opening

Clinical Applications and Risks

Infection Prevention

• Using contaminated bacteriostatic water can introduce pathogens into:

  • Reconstituted medications
  • Medical devices
  • Patient care equipment

• The CDC guidelines emphasize that only sterile water should be used for:

  • Rinsing nebulization devices 1
  • Filling reservoirs of devices used for nebulization 1
  • Rinsing semicritical equipment used on the respiratory tract 1

Medication Stability Concerns

• Some medications reconstituted with bacteriostatic water show reduced stability over time:
  • Lorazepam diluted in bacteriostatic water maintained only 90% of original concentration after 7 days at 4°C 3
  • After 2 weeks, lorazepam concentration dropped to just 1.5% of original at 4°C 3

Common Pitfalls to Avoid

1. Assuming bacteriostatic agents prevent all contamination: The bacteriostatic agent (typically 0.9% benzyl alcohol) inhibits but does not eliminate all bacterial growth

2. Confusing bacteriostatic water with sterile water: These are different products with different storage requirements and uses

3. Using expired or improperly stored bacteriostatic water: This increases risk of introducing pathogens into sterile medications or equipment

4. Failing to label with opening date: Without proper dating, it's impossible to know when the 28-day limit has been reached

Bottom Line

For patient safety, bacteriostatic water should be refrigerated after opening and discarded after 28 days maximum. Room temperature storage significantly increases contamination risk and is not recommended for reuse on subsequent days.