›Orbital or intracranial complication
›First-line antibiotic — no resistance risk factors
›Amoxicillin PO
›500 mg three times daily or 875 mg twice daily
›Duration 5 to 7 days for adults
›Preferred first-line agent per IDSA and AAO-HNS guidelines
›First-line antibiotic — with resistance risk factors
›Amoxicillin-clavulanate PO
›875 mg / 125 mg twice daily
›Alternative 500 mg / 125 mg three times daily
›Duration 5 to 7 days
›Indications — age > 65, recent hospitalization, antibiotic use within past month, immunocompromised, daycare exposure
›High-dose amoxicillin-clavulanate for high penicillin-resistant S. pneumoniae risk
›2000 mg / 125 mg extended-release twice daily
›Duration 5 to 7 days
Antibiotic therapy — penicillin allergy alternatives
›Non-anaphylactic penicillin allergy
›Doxycycline PO
›100 mg twice daily or 200 mg once daily
›Duration 5 days
›Covers ABRS pathogens including resistant strains
›Penicillin anaphylaxis or type I hypersensitivity
›Levofloxacin PO
›500 to 750 mg once daily
›Duration 5 to 7 days
›QT prolongation risk — review concurrent medications
›Moxifloxacin PO
›400 mg once daily
›Duration 5 to 7 days
›QT prolongation risk — avoid in prolonged QT or electrolyte abnormalities
›Agents to avoid
›Azithromycin and clarithromycin — not recommended as monotherapy
›High S. pneumoniae and H. influenzae resistance rates
›TMP-SMX — not recommended for empiric therapy
›High resistance rates
IV antibiotic therapy — complicated and hospitalized patients
›Orbital cellulitis or preseptal cellulitis
›Ampicillin-sulbactam IV
›3 g IV every 6 hours
›Renal dose adjustment when impaired
›Alternative for beta-lactam allergy
›Levofloxacin 750 mg IV once daily plus metronidazole 500 mg IV every 8 hours
›Orbital abscess or intracranial complication
›Ceftriaxone IV
›2 g IV every 12 hours
›Provides CNS penetration for intracranial extension
›Add metronidazole for anaerobic coverage if sinogenic abscess
›500 mg IV every 8 hours
›Add vancomycin when MRSA risk or failed beta-lactam therapy
›15 to 20 mg per kg IV every 8 to 12 hours
›AUC-guided monitoring preferred
›Fungal sinusitis — invasive
›Amphotericin B liposomal IV — first-line for mucormycosis
›5 to 10 mg per kg IV daily
›Urgent surgical debridement in addition to antifungal therapy
›Voriconazole IV for Aspergillus
›6 mg per kg IV every 12 hours for 2 doses then 4 mg per kg every 12 hours
Treatment failure and antibiotic de-escalation
›Treatment failure protocol
›No improvement by 7 days on initial antibiotics
›Switch antibiotic class rather than extending same agent
›CT sinuses to assess for complication or alternative diagnosis
›ENT referral for endoscopy and culture
›Reassess diagnosis at treatment failure
›Viral rhinosinusitis — self-limited and unresponsive to antibiotics
›Allergic rhinitis requiring different management
›Anatomic obstruction requiring surgical correction
›Duration targets
›Uncomplicated ABRS — 5 to 7 days when antibiotic indicated
›Orbital complication with IV antibiotics — 10 to 14 days total course typical
›Intracranial complication — 4 to 6 weeks depending on source control