Acute rhinosinusitis (ARS) is one of the most frequent diagnoses in clinical practice. Common symptoms include anterior and/or posterior nasal drainage, nasal obstruction, and facial pain, pressure, or sensation of fullness. ARS etiology is more often viral than bacterial, and infection-initiated inflammation is the primary pathophysiologic mechanism responsible for symptoms. Because ARS is usually a self-limited process, the primary goal of treatment is symptom relief, which can be more effectively achieved by targeting the underlying inflammation. Intranasal steroids (INS) have been shown to reduce components of respiratory inflammation and increase symptom relief for ARS when used alone or combined with antibiotics. Based on current evidence in support of INS therapy, the European Position Paper on Rhinosinusitis and Nasal Polyps 2007 guidelines and a recent Cochrane meta-analysis recommend using INS in the treatment of ARS, both as monotherapy and as an adjunct to antibiotics.