What are the recommendations for using Ertapenem for treatment?

Ertapenem Treatment Recommendations

FDA-Approved Indications

Ertapenem is indicated for moderate to severe infections in adults and pediatric patients ≥3 months of age, including complicated intra-abdominal infections, complicated skin/skin structure infections (including diabetic foot infections without osteomyelitis), community-acquired pneumonia, complicated urinary tract infections including pyelonephritis, and acute pelvic infections. 1 Additionally, ertapenem is approved for prophylaxis of surgical site infection following elective colorectal surgery in adults. 1

Dosing Regimens

Treatment Dosing

Adults and pediatric patients ≥13 years:

• 1 gram once daily intravenously or intramuscularly 1
• IV infusion must be administered over 30 minutes 1
• IM administration may be used as an alternative for up to 7 days (IV may be used for up to 14 days) 1

Pediatric patients 3 months to 12 years:

• 15 mg/kg twice daily (not to exceed 1 gram/day) 1

Surgical Prophylaxis Dosing

For elective colorectal surgery:

• 1 gram single IV dose given 1 hour prior to surgical incision 1

Treatment Duration by Infection Type

The duration of ertapenem therapy varies significantly by infection type and clinical response:

• Complicated intra-abdominal infections: 5-14 days, with most immunocompetent, non-critically ill patients requiring only 5-7 days if adequate source control is achieved 2, 1
• Complicated skin/skin structure infections: 7-14 days (adult diabetic foot infection patients received up to 28 days including possible oral switch therapy) 1
• Community-acquired pneumonia: 10-14 days, though duration should generally not exceed 8 days in responding patients 3, 2
• Complicated urinary tract infections/pyelonephritis: 10-14 days, with standard duration of 5-7 days for most cases 2, 1
• Acute pelvic infections: 3-10 days 1

Patients can be switched to oral therapy after ≥3 days of parenteral ertapenem if clinically stable (temperature ≤37.8°C, heart rate ≤100 bpm, respiratory rate ≤24 breaths/min, systolic BP ≥90 mmHg, oxygen saturation ≥90%, ability to maintain oral intake, and normal mental status). 2

Special Populations

Renal Impairment

For patients with creatinine clearance >30 mL/min/1.73 m², no dosage adjustment is necessary. 1

For patients with severe renal impairment (CrCl ≤30 mL/min/1.73 m²) or end-stage renal disease (CrCl ≤10 mL/min/1.73 m²):

• Reduce dose to 500 mg once daily 1
• If ertapenem is administered within 6 hours prior to hemodialysis, give a supplementary dose of 150 mg following the hemodialysis session 1
• If administered ≥6 hours prior to hemodialysis, no supplementary dose is needed 1

Hepatic Impairment

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

Clinical Context and Antimicrobial Stewardship

Appropriate Use Scenarios

Ertapenem is particularly valuable for polymicrobial infections involving Enterobacteriaceae and anaerobic bacteria, including complicated intra-abdominal infections, complicated skin/skin structure infections, and acute pelvic infections. 4

For community-acquired pneumonia in hospitalized non-ICU patients, ertapenem is an acceptable β-lactam option when combined with a macrolide (or doxycycline as an alternative), particularly for patients with comorbidities or recent antibiotic exposure. 3

Ertapenem 1 gram once daily is specifically recommended for patients with inadequate/delayed source control or those at high risk of infection with community-acquired ESBL-producing Enterobacteriaceae in intra-abdominal infections. 5

Important Limitations and Caveats

Ertapenem lacks activity against Pseudomonas aeruginosa, Enterococcus species, methicillin-resistant Staphylococcus aureus, and Stenotrophomonas maltophilia, making it unsuitable for nosocomial infections where these pathogens are likely. 6

For patients in septic shock, alternative carbapenems with more frequent dosing should be considered instead of once-daily ertapenem, such as meropenem 1 gram every 6 hours by extended infusion, doripenem 500 mg every 8 hours by extended infusion, or imipenem/cilastatin 500 mg every 6 hours by extended infusion. 3, 5

Broad use of ertapenem may hasten the appearance of carbapenem-resistant Enterobacteriaceae, Pseudomonas, and Acinetobacter species, and its use should be reserved for appropriate clinical scenarios. 3, 2

Targeted Prophylaxis Considerations

In solid organ transplant recipients colonized with ESBL-producing Enterobacteriaceae, ertapenem was mentioned as an acceptable alternative for targeted perioperative antibiotic prophylaxis in selected carriers, though guidelines recommend limiting carbapenem-based prophylaxis due to risk of carbapenemase production. 3

For transrectal ultrasound-guided prostate biopsy in fluoroquinolone-resistant E. coli carriers, targeted prophylaxis regimens may include ertapenem as an alternative to standard fluoroquinolone prophylaxis. 3

Administration Considerations

Intravenous Preparation

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

For IV administration:

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

Intramuscular Preparation

For IM administration:

• Reconstitute 1 gram vial with 3.2 mL of 1.0% lidocaine HCl injection (without epinephrine) 1
• Use reconstituted IM solution within 1 hour after preparation 1
• Administer by deep IM injection into large muscle mass (gluteal muscles or lateral thigh) 1
• IM administration is contraindicated in patients with known hypersensitivity to local anesthetics of the amide type due to lidocaine use 1

Caution should be taken when administering ertapenem intramuscularly to avoid inadvertent injection into a blood vessel. 1

Pharmacokinetic Properties

Ertapenem has a plasma half-life of approximately 4 hours, making it suitable for once-daily administration, compared to other carbapenems with half-lives of approximately 1 hour. 6, 7 The relative bioavailability of the 1 gram IM dose is 92%, and ertapenem does not accumulate following multiple daily doses. 8

Ertapenem is highly protein-bound (approximately 92-95%), with approximately 45% of plasma clearance occurring via renal clearance and the remainder primarily via formation of a β-lactam ring-opened metabolite excreted in urine. 7