Treatment of Peritonsillar Abscess: Ampicillin/Sulbactam (Unasyn) Approach
Ampicillin/sulbactam (Unasyn) is not recommended for treatment of peritonsillar abscess due to high rates of resistance among community-acquired E. coli. 1
Pathophysiology and Microbiology
Peritonsillar abscess is the most common deep infection of the head and neck in adults 2. These infections are typically polymicrobial, involving:
- Group A streptococci (primary pathogen)
- Oral anaerobes
- Various aerobic bacteria
First-Line Treatment Approach
1. Drainage Procedure
- Needle aspiration (gold standard for diagnosis and initial treatment) 3
- Incision and drainage for larger or recurrent abscesses
- In select cases, immediate tonsillectomy may be necessary 3
2. Recommended Antibiotic Therapy
Based on current guidelines, appropriate antibiotics include:
- First choice: Penicillin plus metronidazole OR clindamycin alone 1
- Alternative options:
- Clindamycin (provides excellent anaerobic coverage)
- Cephalosporins (ceftriaxone, cefotaxime)
- Metronidazole (for anaerobic coverage)
3. Adjunctive Therapy
- Corticosteroids: Single high-dose steroid treatment has shown significant benefit in reducing symptoms such as fever, throat pain, dysphagia, and trismus 4
- Pain management: Adequate analgesia is essential
- Hydration: Maintain adequate fluid intake
Why Not Ampicillin/Sulbactam (Unasyn)?
The Infectious Diseases Society of America (IDSA) guidelines specifically state: "Ampicillin-sulbactam is not recommended for use because of high rates of resistance to this agent among community-acquired E. coli" 1. While this statement appears in the context of intra-abdominal infections, the principle applies to head and neck infections as well, where resistance patterns are similar.
Treatment Duration
- Typically 10-14 days of antibiotics
- Parenteral therapy initially, with transition to oral antibiotics after clinical improvement (usually within 48-72 hours)
Special Considerations
- History of multiple peritonsillar abscesses: Consider tonsillectomy after resolution of acute infection 1
- Complications: Monitor for airway obstruction, extension to deep neck spaces, or systemic spread of infection
- Outpatient management: Most patients can be managed as outpatients after successful drainage 2, 5
Follow-up
- Clinical reassessment within 48-72 hours
- Evaluate for resolution of fever, pain, trismus, and dysphagia
- Consider imaging if symptoms persist or worsen
Conclusion
For peritonsillar abscess treatment, drainage procedures combined with appropriate antibiotics (not ampicillin/sulbactam) and supportive care remain the cornerstone of management. Corticosteroids provide additional benefit in symptom management and recovery acceleration.