What is the first-line treatment for acute bacterial sinusitis?

Amoxicillin is considered the first-line treatment for acute bacterial sinusitis, particularly in adults. This is primarily due to its effectiveness against the most common pathogens responsible for the condition, such as Streptococcus pneumoniae and Haemophilus influenzae.

Amoxicillin works well because it is a penicillin-type antibiotic that targets bacterial cell wall synthesis, leading to cell lysis and death of the bacteria. Given its safety profile, efficacy, and relatively low cost, it is often preferred. The recommended duration of treatment is typically 5 to 7 days, but if symptoms persist, the course may be extended or an alternative antibiotic may be considered.

Other antibiotics listed, such as clarithromycin and azithromycin, are alternatives that can be used in patients with penicillin allergies or specific contraindications. However, they are not first-line due to the increased risk of resistance and concerns about adverse effects.

Trimethoprim-sulfamethoxazole can be effective against some bacterial infections but is not a preferred first-line choice for acute bacterial sinusitis. Resistance patterns, effectiveness, and the overall safety profile of the antibiotic all influence why amoxicillin is favored in these cases.