From the Guidelines
Penicillin is the first-line antibiotic for treating Actinomyces infections, with a combination of three antibiotics including penicillin being the recommended treatment. The treatment of Actinomyces infections typically involves high-dose intravenous penicillin G for 2-6 weeks, followed by oral penicillin V or amoxicillin for 6-12 months 1. For penicillin-allergic patients, alternatives include tetracyclines, macrolides, or clindamycin. Some key points to consider when treating Actinomyces infections include:
- The long treatment duration is necessary because Actinomyces infections typically form dense, fibrous lesions with poor antibiotic penetration
- These bacteria are slow-growing anaerobes that form characteristic sulfur granules in infected tissue
- Surgical drainage may be required alongside antibiotics for abscesses or extensive disease
- Treatment response should be monitored clinically, with improvement typically seen within a few weeks, though complete resolution requires the full course of therapy to prevent relapse. It's worth noting that the evidence for the treatment of Actinomyces infections is based on a level of evidence C, indication I, as stated in the guidelines on the diagnosis and management of pericardial diseases executive summary by the European Society of Cardiology 1.
From the FDA Drug Label
Vincent’s infection caused by Fusobacterium fusiforme.Actinomycosis caused by Actinomyces israelii.
- Doxycycline is indicated for the treatment of Actinomycosis caused by Actinomyces israelii 2.
- The antibiotic that treats Actinomycosis is doxycycline.
From the Research
Antibiotic Treatment for Actinomycosis
The following antibiotics are used to treat Actinomycosis:
- Penicillin G 3, 4
- Amoxicillin 3, 4, 5
- Ampicillin 6
- Penicillin V 4
- Amoxicillin/clavulanic acid 4, 5
- Minocycline 7 (for patients allergic to penicillin)
Treatment Duration
The duration of antibiotic therapy for Actinomycosis can vary:
- 6-12 months for penicillin G or amoxicillin 3
- 3 months in patients with optimal surgical resection of infected tissues 3
- 2-6 weeks for intravenous penicillin G, followed by oral penicillin V 4
- 1-4 weeks for a combination of penicillin G and metronidazol 4
- 6 weeks for oral amoxicillin/clavulanic acid 5
- 8-16 weeks for oral minocycline 7