Total Volume When Mixing Ertapenem 1g with 3.2ml of Diluent
When mixing ertapenem 1g with 3.2ml of diluent, the total volume is 4.2ml.
Reconstitution Process for Ertapenem
Ertapenem is a carbapenem antibiotic that requires reconstitution before administration. The process involves:
- Ertapenem 1g powder contributes approximately 1ml to the final volume when reconstituted 1
- Adding 3.2ml of diluent to the powder results in a total volume of 4.2ml 1, 2
- This reconstituted solution contains ertapenem at a concentration of approximately 238mg/ml 2
Clinical Applications of Ertapenem
Ertapenem is used in various clinical scenarios:
- Treatment of intra-abdominal infections at a dose of 1g once daily 1, 2
- Management of complicated urinary tract infections 3
- Treatment of community-acquired pneumonia and acute pelvic infections 4
- Effective against most strains with AmpC and extended-spectrum beta-lactamases 4
Administration Considerations
The reconstituted solution can be administered through different routes:
- Intravenous infusion: The standard 1g dose is typically infused over 30 minutes 5, 6
- Intramuscular injection: The 1g dose has 92% bioavailability compared to IV administration 5
- For IM administration, ertapenem is particularly valuable when vascular access is limited 7
Pharmacokinetic Properties
Understanding the volume is important for proper dosing and administration:
- After IV administration, ertapenem reaches a maximum plasma concentration (Cmax) of approximately 155 mg/L for total drug 4
- The plasma half-life is approximately 4 hours in healthy volunteers 6
- Excretion is largely renal, divided equally between native drug and an open-ring derivative 4
Important Clinical Considerations
When administering reconstituted ertapenem:
- No accumulation occurs after multiple once-daily dosing 6
- For patients with diabetic foot infections, free interstitial concentrations in infected tissue are higher than in healthy tissue 8
- For treatment of established infections, therapy should continue for 4-7 days depending on the patient's immune status and adequacy of source control 2