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

Ertapenem: Indications and Dosing Recommendations

Ertapenem is a once-daily carbapenem antibiotic indicated for the treatment of moderate to severe infections caused by susceptible bacteria, with a standard adult dose of 1 gram once daily. 1

Approved Indications

Adult Indications (FDA-approved):

• Complicated intra-abdominal infections (5-14 days)
• Complicated skin and skin structure infections, including diabetic foot infections without osteomyelitis (7-14 days)
• Community-acquired pneumonia (10-14 days)
• Complicated urinary tract infections, including pyelonephritis (10-14 days)
• Acute pelvic infections including postpartum endomyometritis, septic abortion, and post-surgical gynecologic infections (3-10 days)
• Prophylaxis of surgical site infection following elective colorectal surgery (single dose) 1

Specific Role in Treatment Algorithms:

• First-line therapy for patients with inadequate/delayed source control or at high risk of infection with community-acquired ESBL-producing Enterobacterales 2
• Alternative to piperacillin-tazobactam for complicated intra-abdominal infections 2
• Option for patients with documented beta-lactam allergies (excluding carbapenems) 2

Dosing Recommendations

Adults and Pediatric Patients ≥13 years:

• 1 gram IV or IM once daily 1
• For severe renal impairment (CrCl ≤30 mL/min/1.73 m²): 500 mg once daily
• For end-stage renal disease (CrCl ≤10 mL/min/1.73 m²): 500 mg once daily
• For hemodialysis patients: 150 mg supplementary dose after dialysis if administered within 6 hours before dialysis 1

Pediatric Patients (3 months to 12 years):

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

Route of Administration:

• Intravenous infusion over 30 minutes (preferred)
• Intramuscular injection as alternative (for up to 7 days) 1

Clinical Applications

Intra-abdominal Infections:

• Recommended for patients with inadequate/delayed source control
• Particularly valuable for infections with suspected ESBL-producing organisms 2
• Effective alternative to combination therapy (ceftriaxone plus metronidazole) 3

Skin and Soft Tissue Infections:

• Effective for complicated infections including diabetic foot infections (without osteomyelitis)
• Alternative to vancomycin plus piperacillin-tazobactam or carbapenems for necrotizing infections 2

Community-Acquired Pneumonia:

• Once-daily dosing provides convenience compared to multiple daily dose regimens
• Clinical cure rates comparable to ceftriaxone 4

Special Considerations

Advantages:

• Once-daily dosing improves compliance and reduces nursing time
• Broad spectrum coverage including ESBL-producing organisms 5
• Spares antipseudomonal carbapenems (meropenem, imipenem) for more resistant infections 2

Limitations:

• Not active against Pseudomonas aeruginosa, Acinetobacter species, methicillin-resistant staphylococci, or enterococci 6
• Should not be used for hospital-acquired infections where these pathogens are common

Important Precautions:

• Do not mix or co-infuse with other medications
• Do not use diluents containing dextrose
• Complete IV infusion within 6 hours of reconstitution 1
• Use with caution in patients with CNS disorders due to potential for seizures 1

Practical Administration Tips

• For IV administration: Reconstitute 1g vial with 10 mL of appropriate diluent, then dilute in 50 mL of 0.9% sodium chloride
• For IM administration: Reconstitute with 3.2 mL of 1.0% lidocaine (without epinephrine) and use within 1 hour 1
• When switching from IV to oral therapy after clinical improvement, appropriate oral options depend on the infection type and susceptibility patterns

Ertapenem offers the advantage of once-daily dosing with excellent activity against common community-acquired pathogens, making it particularly valuable for outpatient parenteral antimicrobial therapy and for infections caused by ESBL-producing organisms.