Antibiotics for acute rhinosinusitis in adults.

Acute rhinosinusitis is an acute infection of the nasal passages and paranasal sinuses that lasts less than four weeks. Diagnosis of acute rhinosinusitis is generally based on clinical signs and symptoms in ambulatory care settings. Technical investigations are not routinely performed, nor are they recommended in most countries. Some trials show a trend in favour of antibiotics, but the balance of benefit versus harm is unclear.We merged two Cochrane Reviews for this update, which comprised different approaches with overlapping populations, resulting in different conclusions. For this review update, we maintained the distinction between populations diagnosed by clinical signs and symptoms, or imaging.