Treatment of Bacterial Sinusitis

Amoxicillin or amoxicillin-clavulanate are the first-line treatments for bacterial sinusitis, with treatment duration typically 10-14 days. 1

Diagnosis and Timing of Antibiotic Therapy

Bacterial sinusitis should be distinguished from viral sinusitis based primarily on duration of illness, with bacterial infection uncommon in patients with symptoms lasting less than 10 days 2
Diagnosis of acute bacterial sinusitis may be made in patients with symptoms of a viral upper respiratory infection that has not improved after 10 days or has worsened after 5-7 days 2, 1
Delaying antibiotic treatment until symptoms persist for at least 7-10 days helps identify patients with bacterial infections who are most likely to benefit from antibiotics 2

Amoxicillin is generally recommended as the first-line empiric treatment for uncomplicated bacterial sinusitis 2, 1
Amoxicillin-clavulanate is preferred in regions with high bacterial resistance, for more severe cases, or when beta-lactamase producing pathogens are suspected 1, 3
For adults, the recommended dose is 500-875 mg of amoxicillin-clavulanate twice daily 1
For children, the recommended dose is 22.5-45 mg/kg of amoxicillin-clavulanate twice daily (based on amoxicillin component) 1

For penicillin-allergic patients, second-generation cephalosporins (cefuroxime) or third-generation cephalosporins (cefpodoxime) are appropriate alternatives 1, 4
Macrolides such as azithromycin or clarithromycin may be used in cases of serious drug allergy 1, 4
Respiratory fluoroquinolones like levofloxacin are approved for acute bacterial sinusitis but should be reserved for cases where other options cannot be used 5

Standard duration of antibiotic treatment is 10-14 days for most antibiotics 2, 1
Some newer agents may be effective with shorter courses (5-7 days) 2, 6
Treatment should continue until the patient is symptom-free for 7 days 1

Reassess treatment response within 72 hours of initiating antibiotics 2
If symptoms persist or worsen after 3-5 days of initial treatment, consider changing to an alternative antibiotic 2, 1
If there is no improvement after 72 hours, this suggests either incorrect diagnosis, resistant pathogens, or a non-infectious cause 2

Intranasal corticosteroids may be helpful as an adjunct to antibiotic therapy, particularly in recurrent acute and chronic sinusitis 2, 1
Other symptomatic treatments such as decongestants, antihistamines, saline irrigation, mucolytics, and expectorants may provide benefit in selected cases 2, 1

Patients with a history of recurrent bacterial sinusitis may warrant immediate antibiotic therapy rather than delayed treatment 2
Patients with poor oro-dental condition or recent antibiotic use may derive greater benefit from antibiotic treatment 7
For severe cases with complications (orbital involvement, neurological symptoms), hospitalization and parenteral antibiotics may be necessary 2, 1
Consultation with a specialist is recommended for sinusitis that is refractory to standard antibiotic treatment, recurrent sinusitis, or sinusitis with unusual opportunistic infections 2

Overdiagnosis of bacterial sinusitis and unnecessary antibiotic treatment is common 2, 8
Viral upper respiratory infections are often mistaken for bacterial sinusitis, leading to inappropriate antibiotic use 2, 7
Most cases of untreated acute sinusitis resolve spontaneously, but antibiotics reduce the risk of treatment failure within 10 days 7
Failure to consider resistant pathogens when initial therapy fails can lead to prolonged symptoms and complications 3