What is the recommended dose of Amoxicillin-Clavulanate (Augmentin) for acute sinusitis?

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From the Guidelines

For adults with sinusitis, the typical amoxiclav (amoxicillin-clavulanate) dose is 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, as supported by the most recent evidence 1. The choice of amoxiclav dose is based on its effectiveness in treating sinusitis, which is attributed to the combination of amoxicillin with clavulanic acid, helping to overcome bacterial resistance by inhibiting beta-lactamase enzymes that would otherwise destroy the antibiotic. Some key points to consider when prescribing amoxiclav for sinusitis include:

  • Taking the medication with food to reduce stomach upset
  • Completing the entire course even if symptoms improve before finishing
  • Monitoring for common side effects such as diarrhea, nausea, and rash
  • Seeking medical attention immediately if severe diarrhea, severe abdominal pain, or allergic reactions like hives or difficulty breathing occur Additional measures to support recovery alongside antibiotic treatment include staying hydrated and using saline nasal irrigation. It is essential to note that the duration of antibiotic therapy for sinusitis is not well defined, but a 10- to 14-day course might be adequate for most patients with acute disease, as suggested by 1 and 1.

From the Research

Amoxiclav Dose for Sinusitis

  • The standard dose of amoxicillin/clavulanate for acute bacterial sinusitis is 875 mg/125 mg every 12 hours 2.
  • A study comparing high-dose versus standard-dose amoxicillin/clavulanate found no significant difference in efficacy between the two groups 3.
  • Another study found that adults with clinically diagnosed acute bacterial sinusitis were more likely to improve rapidly when treated with high-dose amoxicillin/clavulanate, but not when treated with extended-release high-dose amoxicillin/clavulanate 4.
  • The efficacy of amoxicillin/clavulanate has also been compared to azithromycin, with one study finding that azithromycin had a faster resolution of signs and symptoms of sinusitis 5.
  • A different study found that more patients randomized to azithromycin extended release experienced symptom resolution at day 5 than those randomized to amoxicillin/clavulanate, without experiencing differences in second antibiotic use at 28 days 6.

Dosage Regimens

  • Amoxicillin/clavulanate can be given every 12 hours (875 mg/125 mg) or every 8 hours (500 mg/125 mg) for the treatment of acute bacterial maxillary sinusitis, with similar efficacy and safety profiles 2.
  • Azithromycin has been shown to be effective in a 3-day course (500 mg once daily) for the treatment of acute sinusitis, with a faster resolution of signs and symptoms compared to a 10-day course of amoxicillin/clavulanate 5.

Adverse Effects

  • Diarrhea is a common adverse effect of amoxicillin/clavulanate, with severe diarrhea reported in 7.0% of patients receiving standard-dose amoxicillin/clavulanate and 7.7% of patients receiving high-dose amoxicillin/clavulanate 3.
  • High-dose amoxicillin/clavulanate has been associated with a higher incidence of severe diarrhea compared to standard-dose amoxicillin/clavulanate 4.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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