Meropenem 3-Hour Infusion Preparation and Storage Protocol
Dilution Procedure
For 3-hour infusions every 8 hours, reconstitute meropenem vials with Sterile Water for Injection, then further dilute in a compatible IV infusion fluid for administration. 1
Reconstitution Steps
- Add 10 mL of Sterile Water for Injection to 500 mg vials or 20 mL to 1 gram vials 1
- Shake to dissolve and let stand until clear, yielding approximately 50 mg/mL concentration 1
- After reconstitution, add the solution to an IV container and further dilute with an appropriate infusion fluid for the 3-hour infusion 1
Storage of Diluted Solutions
Freshly prepared solutions should be used preferentially, but reconstituted meropenem maintains adequate potency for limited periods under specific temperature conditions. 1
Storage Time Limits
- At room temperature (up to 25°C/77°F): Use within 3 hours 1
- Refrigerated (up to 5°C/41°F): Use within 13 hours 1
- Never freeze meropenem solutions 1
Practical Workflow for Every-8-Hour Dosing
Given the 3-hour infusion duration and 8-hour dosing interval, you have a 5-hour window between infusions. The storage limitations create specific constraints:
- Prepare each dose fresh immediately before administration when possible, as this is the FDA-recommended approach 1
- If preparing doses in advance is necessary, refrigerate the diluted solution and use within 13 hours, which accommodates the next scheduled dose 1
- Do not prepare more than one dose ahead due to the 13-hour refrigerated stability limit 1
Critical Stability Considerations
- Meropenem is inherently unstable, particularly during prolonged storage 2
- The 3-hour extended infusion is specifically recommended for resistant organisms (MIC ≥8 mg/L) or carbapenem-resistant Enterobacteriaceae infections to optimize pharmacodynamic targets 2, 3, 4
- Solutions should be inspected visually for particulate matter and discoloration before each administration 1
Compatibility Warning
Do not mix meropenem with other drugs or add it to solutions containing other medications, as compatibility has not been established 1