What are the first-line antibiotics for acute sinusitis (sinus infection)?

From the Guidelines

The first-line antibiotic treatment for acute bacterial sinusitis is typically amoxicillin or amoxicillin-clavulanate, with the preferred dosage being 500 mg three times daily or 875 mg twice daily for 5-10 days, as recommended by the American College of Physicians and the Centers for Disease Control and Prevention 1.

Key Considerations

• The American Academy of Otolaryngology–Head and Neck Surgery emphasizes watchful waiting (without antibiotic therapy) as initial management for all patients with uncomplicated ABRS, regardless of severity 1.
• Amoxicillin-clavulanate is the preferred agent, and doxycycline or a respiratory fluoroquinolone may be used as an alternative in patients with ABRS 1.
• Patients who are seriously ill, who deteriorate clinically despite antibiotic therapy, or who have recurrent episodes should be referred to a specialist (for example, an otolaryngologist, infectious disease specialist, or allergist) 1.

Treatment Approach

• Treatment should be continued for 5-10 days, with most patients showing improvement within 48-72 hours.
• Antibiotics should only be prescribed for suspected bacterial infections, typically when symptoms persist beyond 10 days, are severe, or worsen after initial improvement.
• Supportive measures like saline irrigation, decongestants, and pain relievers can help manage symptoms while antibiotics address the underlying infection.

Alternatives for Penicillin Allergy

• For patients with penicillin allergy, alternatives include doxycycline (100 mg twice daily), levofloxacin (500 mg once daily), or moxifloxacin (400 mg once daily) 1.

Minimizing Antibiotic Resistance

• This approach targets the most common bacterial pathogens in sinusitis (Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis) while minimizing unnecessary antibiotic use that could contribute to resistance 1.

From the FDA Drug Label

1. 4 Acute Bacterial Sinusitis: 5 Day and 10 to 14 Day Treatment Regimens Levofloxacin is approved for the treatment of acute bacterial sinusitis (ABS) using either 750 mg by mouth x 5 days or 500 mg by mouth once daily x 10 to 14 days To evaluate the safety and efficacy of a high dose short course of levofloxacin, 780 outpatient adults with clinically and radiologically determined acute bacterial sinusitis were evaluated in a double-blind, randomized, prospective, multicenter study comparing levofloxacin 750 mg by mouth once daily for five days to levofloxacin 500 mg by mouth once daily for 10 days Clinical success rates (defined as complete or partial resolution of the pre-treatment signs and symptoms of ABS to such an extent that no further antibiotic treatment was deemed necessary) in the microbiologically evaluable population were 91.4% (139/152) in the levofloxacin 750 mg group and 88.6% (132/149) in the levofloxacin 500 mg group at the test-of-cure (TOC) visit (95% CI [-4. 2,10] for levofloxacin 750 mg minus levofloxacin 500 mg).

First line antibiotics for sinus infection are:

• Levofloxacin 750 mg by mouth x 5 days
• Levofloxacin 500 mg by mouth once daily x 10 to 14 days 2

From the Research

First-Line Antibiotics for Sinus Infection

The following antibiotics are commonly used as first-line treatments for sinus infections:

• Amoxicillin 3, 4
• Amoxicillin-clavulanate 3, 5, 4, 6
• Levofloxacin 5
• Moxifloxacin 7
• Cefuroxime, cefpodoxime, or cefdinir 3
• Doxycycline or a respiratory fluoroquinolone for patients with a beta-lactam allergy 4
• Clindamycin plus a third-generation cephalosporin for children with non-type I hypersensitivity to beta-lactam antibiotics 4

Treatment Duration and Dosage

The optimal duration of therapy is unknown, but some recommend treatment until the patient becomes free of symptoms and then for an additional 7 days 3. The dosage of amoxicillin plus clavulanate can be either standard-dose or high-dose, but a randomized clinical trial found no significant difference in efficacy between the two 6.

Efficacy and Safety

Studies have shown that amoxicillin is as effective as amoxicillin-clavulanate as a first-line treatment for acute bacterial rhinosinusitis for those without a beta-lactam allergy 4. Moxifloxacin and levofloxacin have also been found to be effective and safe in the treatment of acute sinusitis 5, 7. However, the frequency of drug-related adverse events, such as nausea and diarrhea, can vary between different antibiotics 5, 7.