Treatment of Anaerobic Gram-Positive Rod Infections

First-Line Treatment Options

The Infectious Diseases Society of America recommends clindamycin as the first-line treatment for anaerobic gram-positive rod infections due to its excellent activity against most gram-positive anaerobes, including Peptostreptococcus species and Clostridium species 1, 2
Clindamycin is recommended at a dose of 600-900 mg IV every 8 hours for severe infections or 300 mg oral three times daily for mild-to-moderate infections 1, 3

For mild-to-moderate infections, the American College of Clinical Pharmacy recommends oral clindamycin 300 mg three times daily for 7-10 days 3
For severe infections, the Infectious Diseases Society of America recommends IV clindamycin 600-900 mg every 8 hours 1, 4
Alternative options for severe infections include ampicillin-sulbactam 1.5-3.0 g IV every 6-8 hours, imipenem/cilastatin 1 g IV every 6-8 hours, meropenem 1 g IV every 8 hours, and ertapenem 1 g IV daily 2, 5

For patients with penicillin allergy, the Infectious Diseases Society of America recommends using clindamycin or metronidazole with an aminoglycoside or fluoroquinolone 2, 3
For mixed infections, the Infectious Diseases Society of America recommends combination therapy with ampicillin-sulbactam plus clindamycin plus ciprofloxacin, or alternative therapy with cefotaxime plus metronidazole or clindamycin 1, 2