What are the indications and dosing guidelines for ertapenem?

Indications and Dosing Guidelines for Ertapenem

Ertapenem is indicated for moderate to severe infections at a standard adult dose of 1 gram once daily, with specific indications including complicated intra-abdominal infections, complicated skin and skin structure infections, community-acquired pneumonia, complicated urinary tract infections, and acute pelvic infections. 1

Approved Indications

• Complicated intra-abdominal infections: 1g once daily for 5-14 days 1, 2
• Complicated skin and skin structure infections (including diabetic foot infections without osteomyelitis): 1g once daily for 7-14 days 1
• Community-acquired pneumonia: 1g once daily for 10-14 days 1
• Complicated urinary tract infections (including pyelonephritis): 1g once daily for 10-14 days 1
• Acute pelvic infections (including postpartum endomyometritis, septic abortion, and post-surgical gynecologic infections): 1g once daily for 3-10 days 1
• Surgical prophylaxis: Single 1g dose given 1 hour prior to elective colorectal surgery 1

Antimicrobial Spectrum

Ertapenem is particularly valuable for:

• Infections caused by ESBL-producing Enterobacterales 2, 3
• Mixed aerobic/anaerobic infections 4, 2
• Community-acquired infections requiring broad-spectrum coverage 2

Important spectrum limitations:

• Not active against Pseudomonas aeruginosa, Acinetobacter species, methicillin-resistant staphylococci, or enterococci 2
• Should not be used for hospital-acquired infections where these pathogens are common 2

Dosing Guidelines

Adults and Children ≥13 years:

• Standard dose: 1 gram IV or IM once daily 1
• Administration:
  • IV infusion over 30 minutes 1
  • May be given IM when IV administration is not feasible 1
  • IV therapy may be administered for up to 14 days 1
  • IM therapy may be administered for up to 7 days 1

Children 3 months to 12 years:

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

Renal Impairment (Adults):

• CrCl >30 mL/min/1.73m²: No dosage adjustment needed 1
• CrCl ≤30 mL/min/1.73m²: 500 mg once daily 1
• Hemodialysis: 500 mg daily + supplementary dose of 150 mg if administered within 6 hours prior to hemodialysis 1

Special Clinical Scenarios

Intra-abdominal Infections

Ertapenem (1g q24h) is recommended for patients with:

• Inadequate/delayed source control 4
• High risk of infection with community-acquired ESBL-producing Enterobacterales 4

Necrotizing Infections of Skin, Fascia, and Muscle

Ertapenem (1g q24h) is listed as an appropriate monotherapy option for mixed infections 4

Administration Considerations

• Do not mix or co-infuse with other medications 1
• Do not use diluents containing dextrose 1
• For IV administration: Reconstitute 1g vial with 10mL of appropriate diluent, then dilute in 50mL of 0.9% sodium chloride 1
• For IM administration: Reconstitute with 3.2mL of 1.0% lidocaine HCl (without epinephrine) 1
• Once-daily dosing improves compliance and reduces nursing time, making it convenient for outpatient parenteral antimicrobial therapy 2

Important Precautions

• Monitor for hypersensitivity reactions, especially in patients with beta-lactam allergies 1
• Use with caution in patients with seizure disorders; ertapenem may lower valproic acid levels 1
• Monitor for Clostridioides difficile-associated diarrhea 1
• To reduce development of drug resistance, use only for proven or strongly suspected bacterial infections 1

Ertapenem's once-daily dosing and broad spectrum against common community-acquired pathogens (including ESBL-producers) make it a valuable option for both inpatient and outpatient parenteral antimicrobial therapy, while sparing antipseudomonal carbapenems for more resistant infections.