What are the indications and dosing guidelines for Ertapenem (a carbapenem antibiotic)?

Ertapenem: Indications and Dosing Guidelines

Primary Indications

Ertapenem is a once-daily carbapenem antibiotic indicated for moderate to severe community-acquired infections including complicated intra-abdominal infections, complicated skin/skin structure infections (including diabetic foot infections without osteomyelitis), community-acquired pneumonia, complicated urinary tract infections, and acute pelvic infections. 1

Approved Treatment Indications

• Complicated intra-abdominal infections 1
• Complicated skin and skin structure infections, including diabetic foot infections without osteomyelitis 1
• Community-acquired pneumonia 1
• Complicated urinary tract infections including pyelonephritis 1
• Acute pelvic infections (postpartum endomyometritis, septic abortion, post-surgical gynecologic infections) 1
• Prophylaxis of surgical site infection following elective colorectal surgery (adults only) 1

Specific Clinical Scenarios for Ertapenem Use

Ertapenem 1 g once daily is specifically recommended for patients at high risk of infection with community-acquired ESBL-producing Enterobacterales or those with inadequate/delayed source control. 2

• For complicated cholecystitis with inadequate/delayed source control or high ESBL risk: Ertapenem 1 g q24h 2
• For acute cholangitis with inadequate/delayed source control or high ESBL risk: Ertapenem 1 g q24h 2
• For non-critically ill patients with community-acquired intra-abdominal infections at risk for ESBL-producing Enterobacteriaceae: Ertapenem 1 g every 24 hours 2

Standard Dosing Regimens

Adults and Pediatric Patients ≥13 Years

The standard dose is 1 gram IV or IM once daily, with IV infusion administered over 30 minutes. 1

• IV administration: May be used for up to 14 days 1
• IM administration: May be used for up to 7 days 1

Pediatric Patients 3 Months to 12 Years

Administer 15 mg/kg twice daily (not to exceed 1 g/day) IV or IM. 1

Prophylaxis Dosing (Adults Only)

For elective colorectal surgery: 1 gram single IV dose given 1 hour prior to surgical incision. 1

Duration of Therapy by Indication

Intra-Abdominal Infections

• Immunocompetent, non-critically ill patients with adequate source control: 4 days 2, 3
• Immunocompromised or critically ill patients with adequate source control: Up to 7 days based on clinical conditions and inflammatory markers 2, 3
• Standard duration range: 5-14 days 1

Skin and Skin Structure Infections

• Standard duration: 7-14 days 1
• Diabetic foot infections: Up to 28 days (parenteral or parenteral plus oral switch therapy) 1

Community-Acquired Pneumonia

• Standard duration: 10-14 days, including possible switch to oral therapy after at least 3 days of parenteral therapy once clinical improvement demonstrated 1

Complicated Urinary Tract Infections

• Standard duration: 10-14 days, including possible switch to oral therapy after at least 3 days of parenteral therapy once clinical improvement demonstrated 1

Acute Pelvic Infections

• Standard duration: 3-10 days 1

Dosing Adjustments

Renal Impairment (Adults)

For creatinine clearance >30 mL/min/1.73 m²: No dosage adjustment necessary. 1

For severe renal impairment (CrCl ≤30 mL/min/1.73 m²) and end-stage renal disease (CrCl ≤10 mL/min/1.73 m²): Reduce dose to 500 mg daily. 1

Hemodialysis Patients

If ertapenem is administered within 6 hours prior to hemodialysis: Give supplementary dose of 150 mg following the hemodialysis session. 1

If ertapenem is given at least 6 hours prior to hemodialysis: No supplementary dose needed. 1

• No data available for pediatric patients on hemodialysis 1
• No data for patients on peritoneal dialysis or hemofiltration 1

Hepatic Impairment

No dose adjustment recommendations can be made due to insufficient data. 1

Antimicrobial Spectrum and Activity

Ertapenem has broad-spectrum activity against aerobic and anaerobic Gram-positive and Gram-negative bacteria, with particular strength against ESBL-producing Enterobacteriaceae. 4, 5

Strong Activity Against:

• Most Enterobacteriaceae including ESBL-producing strains 4, 5, 6
• Anaerobic organisms including Bacteroides fragilis group 4, 6
• Drug-resistant Streptococcus pneumoniae 4
• Methicillin-susceptible Staphylococcus aureus 6

Limited or No Activity Against:

• Pseudomonas aeruginosa 4, 5, 6
• Acinetobacter species 5, 6
• Methicillin-resistant staphylococci 6
• Enterococci 5, 6

Critical Clinical Considerations

When NOT to Use Ertapenem

For septic shock or critically ill patients requiring anti-pseudomonal coverage, use alternative carbapenems with more frequent dosing instead of ertapenem. 2, 3

Preferred alternatives for septic shock:

• Meropenem 1 g q6h by extended infusion or continuous infusion 2
• Doripenem 500 mg q8h by extended infusion or continuous infusion 2
• Imipenem/cilastatin 500 mg q6h by extended infusion 2

Monitoring and Treatment Adjustment

Monitor for clinical response and resolution of sepsis markers; if infection persists beyond 7 days, pursue further diagnostic evaluation. 2, 3

Preparation and Administration

Intravenous Administration

DO NOT MIX OR CO-INFUSE WITH OTHER MEDICATIONS. DO NOT USE DILUENTS CONTAINING DEXTROSE. 1

• Reconstitute 1 g vial with 10 mL of Water for Injection, 0.9% Sodium Chloride, or Bacteriostatic Water 1
• Transfer to 50 mL of 0.9% Sodium Chloride Injection 1
• Infuse over 30 minutes 1
• Complete infusion within 6 hours of reconstitution 1

Intramuscular Administration

• Reconstitute 1 g vial with 3.2 mL of 1.0% lidocaine HCl injection (without epinephrine) 1
• Administer by deep IM injection into large muscle mass 1
• Use within 1 hour after preparation 1

Contraindications

Ertapenem is contraindicated in patients with known hypersensitivity to any component or anaphylactic reactions to β-lactams. 1

IM administration is contraindicated in patients with hypersensitivity to local anesthetics of the amide type (due to lidocaine diluent). 1

Important Warnings

Drug Interactions

Co-administration with valproic acid or divalproex sodium reduces valproic acid serum concentrations, potentially increasing breakthrough seizure risk; this combination is generally not recommended. 1

Co-administration with probenecid inhibits renal excretion of ertapenem and is not recommended. 1

Adverse Effects

• Most common (≥5%) in adults: diarrhea, nausea, headache, infused vein complication 1
• Most common (≥5%) in pediatrics: diarrhea, vomiting, infusion site pain 1
• Seizures and CNS adverse events have been reported 1
• Clostridioides difficile-associated diarrhea can occur; evaluate if diarrhea develops 1

Special Precautions

Carbapenems including ertapenem are particularly unstable after reconstitution and should not be stored for extended periods. 7

When administering IM, use caution to avoid inadvertent injection into a blood vessel. 1