Is Amoxicillin-Clavulanate (Augmentin) effective for treating sinusitis?

From the Guidelines

Amoxicillin-clavulanate is recommended as a first-line treatment for bacterial sinusitis in adults with a high risk of being infected by an organism resistant to amoxicillin, with a typical dosage of 875 mg amoxicillin/125 mg clavulanic acid taken twice daily, or 500 mg amoxicillin/125 mg clavulanic acid taken three times daily, for 5-7 days. The decision to prescribe amoxicillin-clavulanate instead of amoxicillin alone is based on factors such as recent antibiotic use, close contact with treated individuals, failure of prior antibiotic therapy, and presence of comorbidity or extremes of life 1.

Key Considerations

• The use of high-dose amoxicillin with clavulanate (2 g orally twice daily or 90 mg/kg/d orally twice daily) is recommended for adults with ABRS who are at a high risk of being infected with an amoxicillin-resistant organism 1.
• Amoxicillin-clavulanate is particularly useful for sinusitis because it covers common respiratory pathogens including Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis, including beta-lactamase producing strains.
• The clavulanic acid component inhibits bacterial beta-lactamase enzymes that would otherwise break down amoxicillin, making this combination more effective against resistant bacteria.

Management Strategies

• Most patients with acute rhinosinusitis should be managed with supportive care, including analgesics for pain and antipyretics for fever 1.
• Additional therapies that may provide symptomatic relief include systemic or topical decongestants, saline nasal irrigation, mucolytics, intranasal corticosteroids, and antihistamines tailored to the patient's symptoms.
• Clinicians should reserve antibiotic treatment for acute rhinosinusitis for patients with persistent symptoms for more than 10 days, onset of severe symptoms or signs of high fever (>39 °C) and purulent nasal discharge or facial pain lasting for at least 3 consecutive days, or onset of worsening symptoms following a typical viral illness that lasted 5 days that was initially improving (double sickening) 1.

Side Effects and Precautions

• Common side effects of amoxicillin-clavulanate include diarrhea, nausea, and rash.
• Probiotics may help reduce antibiotic-associated diarrhea.
• Contact a healthcare provider if symptoms worsen or don't improve after 3 days of treatment.

From the FDA Drug Label

Amoxicillin and clavulanate potassium tablets USP is a combination penicillin-class antibacterial and beta-lactamase inhibitor indicated in the treatment of infections due to susceptible isolates of the designated bacteria in the conditions listed below*: 1.3 Sinusitis – caused by beta-lactamase–producing isolates of H. influenzae and M. catarrhalis.

Amoxicillin-clavulanate is indicated for the treatment of sinusitis caused by beta-lactamase–producing isolates of Haemophilus influenzae and Moraxella catarrhalis 2.

• Key points:
  • The drug is effective against beta-lactamase–producing bacteria.
  • It is used to treat sinusitis caused by H. influenzae and M. catarrhalis.

From the Research

Amoxicillin Clavulin Sinusitis Treatment

• The use of amoxicillin with clavulanate is a recommended treatment for acute bacterial sinusitis in adults, as stated in the study 3.
• A randomized clinical trial compared the effectiveness of standard-dose and high-dose amoxicillin/clavulanate in treating acute bacterial sinusitis, and found that adults with clinically diagnosed acute bacterial sinusitis were more likely to improve rapidly when treated with high-dose immediate-release amoxicillin/clavulanate than with standard-dose, but not when treated with extended-release high-dose amoxicillin/clavulanate 3.
• Another study suggests that therapy for acute bacterial sinusitis may be initiated with high-dose amoxicillin or amoxicillin-clavulanate, and that amoxicillin-clavulanate is an appropriate alternative for penicillin-allergic patients or those who are unresponsive to amoxicillin 4.
• A systematic review of treatments for acute sinusitis found that antibiotics, including amoxicillin and amoxicillin-clavulanic acid, were effective in improving symptoms, but the quality of evidence was generally low 5.
• The Cochrane database of systematic reviews found that penicillin or amoxicillin for 7 to 14 days is supported by current evidence for the treatment of acute maxillary sinusitis confirmed radiographically or by aspiration, but clinicians should weigh the moderate benefits of antibiotic treatment against the potential for adverse effects 6, 7.

Dosage and Administration

• The study 3 used a standard-dose of 875/125 mg of amoxicillin/clavulanate and a high-dose of 2000 mg of extended-release amoxicillin with 125 mg of immediate-release clavulanate twice a day, which was later revised to 1750 mg of immediate-release amoxicillin twice a day.
• 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 4.

Side Effects

• The major side effect of severe diarrhea was reported by 7.4% of high-dose patients and 5.7% of standard-dose patients in one study 3.
• Another study found that dropouts due to adverse effects were significantly lower for cephalosporin antibiotics compared to amoxicillin-clavulanate 6, 7.