From the Guidelines
The recommended dose of amoxicillin for acute bacterial bronchitis in adults is typically 500 mg three times daily or 875 mg twice daily for 5 days, as suggested by the most recent clinical guidelines 1. For children, the dosage is usually calculated based on weight, with 45-90 mg/kg/day divided into two or three doses. Before starting treatment, it's essential to confirm a bacterial cause, as most bronchitis cases are viral and don't require antibiotics. Patients should take the full course of antibiotics even if symptoms improve before completion. Common side effects include diarrhea, nausea, and rash. Those with penicillin allergy should inform their healthcare provider, as alternative antibiotics would be needed. Amoxicillin works by inhibiting bacterial cell wall synthesis, causing bacterial cell death. It's effective against many respiratory pathogens, including Streptococcus pneumoniae and Haemophilus influenzae, common causes of bacterial bronchitis. Key considerations in managing acute bronchitis include distinguishing it from pneumonia and recognizing that the presence of purulent sputum does not necessarily indicate a bacterial infection 1. Given the potential for increased adverse events with antibiotic use, as noted in several studies 1, limiting antibiotic treatment to cases with a high likelihood of bacterial infection is crucial. The American College of Physicians' best practice advice emphasizes the importance of limiting antibiotic treatment duration to 5 days for patients with COPD exacerbations and acute uncomplicated bronchitis who show clinical signs of a bacterial infection 1.
From the Research
Amoxicillin Dose for Acute Bacterial Bronchitis
- The recommended dose of amoxicillin for acute bacterial bronchitis is not explicitly stated in the provided studies, but we can look at the doses used in the treatment of acute exacerbations of chronic bronchitis for guidance.
- A study from 2005 2 used amoxicillin 875 mg/clavulanate 125 mg twice daily for 10 days to treat complicated patients with acute bacterial exacerbation of chronic bronchitis.
- Another study from 1993 3 compared the efficacy and safety of fleroxacin with amoxicillin 500 mg administered every 8 hours for 7 days in the treatment of acute exacerbation of chronic bronchitis.
- A study from 1987 4 compared two versus three daily doses of amoxycillin in bronchitis, with patients receiving either 1000 mg amoxycillin twice daily or 750 mg three times daily.
- A more recent study from 2005 5 used pharmacokinetically enhanced amoxicillin-clavulanate at 2,000/125 mg twice daily for 5 days to treat acute exacerbations of chronic bronchitis, and found it to be as effective as a longer, 7-day course of conventional amoxicillin-clavulanate at 875/125 mg twice daily.
- While these studies do not directly address the treatment of acute bacterial bronchitis, they suggest that amoxicillin doses ranging from 500 mg to 2,000 mg per day, given in divided doses, may be effective in treating respiratory tract infections 3, 4, 5, 6.
Key Findings
- Amoxicillin 875 mg/clavulanate 125 mg twice daily for 10 days was used to treat complicated patients with acute bacterial exacerbation of chronic bronchitis 2.
- Amoxicillin 500 mg administered every 8 hours for 7 days was compared with fleroxacin in the treatment of acute exacerbation of chronic bronchitis 3.
- Pharmacokinetically enhanced amoxicillin-clavulanate at 2,000/125 mg twice daily for 5 days was found to be as effective as a longer, 7-day course of conventional amoxicillin-clavulanate at 875/125 mg twice daily 5.
Treatment Considerations
- The choice of amoxicillin dose and duration of treatment may depend on the severity of the infection, the presence of underlying medical conditions, and the susceptibility of the causative pathogens 2, 3, 5.
- Amoxicillin should be used in conjunction with clavulanate to enhance its spectrum of activity and prevent the development of resistance 2, 5.