What is the shelf life of compounded injectable medication?

Shelf Life of Compounded Injectable Medications

Compounded injectable medications should be stored at 4°C (refrigerated) and used within the timeframes specified by USP Chapter 797 guidelines based on their risk level, with a maximum of 45 days for properly tested preparations.

Storage Requirements and Beyond-Use Dating

The shelf life (beyond-use date) of compounded injectable medications depends primarily on:

1. Risk level classification
2. Storage conditions
3. Sterility testing status

Standard Beyond-Use Dating by Risk Level

When a comprehensive sterility testing program is NOT in place:

• Low-risk preparations:

  • 48 hours at room temperature
  • 14 days when refrigerated (2-8°C)
  • 45 days when frozen (-20°C or below)

• Medium-risk preparations:

  • 30 hours at room temperature
  • 9 days when refrigerated
  • 45 days when frozen

• High-risk preparations:

  • 24 hours at room temperature
  • 3 days when refrigerated
  • 45 days when frozen

When a sterility testing program IS in place, longer beyond-use dates may be assigned based on USP Chapter 795 guidelines for stability 1.

Factors Affecting Stability

Several factors influence the stability and shelf life of compounded injectable medications:

• Temperature: Refrigeration at 4°C is generally recommended to maintain stability and reduce contamination risk 2
• Light exposure: Some medications are photosensitive
• Container type: Glass vs. plastic
• Preservatives: Presence or absence affects stability
• Ingredient compatibility: Some components may interact and reduce stability

Safety Considerations

The 2012-2013 fungal meningitis outbreak caused by contaminated compounded methylprednisolone injections (resulting in 751 infections and 64 deaths) highlights the critical importance of proper sterile compounding practices 3.

Key safety measures include:

• Strict adherence to USP Chapter 797 guidelines
• Proper training of compounding personnel
• Regular quality control testing
• Appropriate storage conditions

Special Considerations for Different Types of Injectables

Parenteral Nutrition Solutions

For home parenteral nutrition (PN), stability can be achieved for:

• 14-21 days when properly prepared and stored at 4°C 4

The ESPGHAN/ESPEN/ESPR/CSPEN guidelines recommend:

• PN for home use should ideally be provided in a single-bag system
• Bags should be stored at 4°C from production until administration
• A dedicated refrigerator should be used for storage 4

Methacholine Solutions

For diagnostic methacholine solutions:

• When prepared with saline diluent and stored at 4°C, concentrations of 0.125 mg/ml and greater should remain stable for 3 months
• When prepared with phenol-containing saline, follow package insert recommendations (typically 2 weeks) 4

Best Practices for Handling

1. Allow refrigerated medications to warm to room temperature before administration for patient comfort 2
2. Inspect for any visible changes (clumping, frosting, precipitation, or changes in clarity/color) before use
3. Discard any unused medication remaining in a nebulizer or syringe after use 4
4. Use sterile technique during preparation and administration

Regulatory Framework

The Drug Quality and Security Act (DQSA) of 2013 improved regulation of compounding pharmacies following the 2012-2013 fungal infections outbreak 3. This legislation created a voluntary registration category for outsourcing facilities that compound sterile drugs.

Conclusion

Proper storage and adherence to beyond-use dating guidelines are essential for maintaining the safety and efficacy of compounded injectable medications. When in doubt about the stability of a compounded injectable medication, consult with a pharmacist or refer to specific stability data for the particular formulation.