Background: Nasal polyposis is an inflammatory disorder involving the mucosa of the nose and paranasal sinuses and affecting approximately 2–4% of the general population. Methods: A literature search of Medline and Embase was conducted to obtain an overview of the epidemiology, pathophysiology, and current treatment of nasal polyposis, focusing on evidence-based efficacy of intranasal corticosteroids (INSs) as primary and postoperative therapy. Recent research on INSs in nasal polyp treatment, along with notable historic findings, was reviewed. Results: Nasal polyps are mostly characterized by eosinophil infiltration, a complex inflammation of nasal mucosa, and possibly production of polyclonal IgE. Current treatment modalities include INSs, oral corticosteroids, and surgery; surgery is generally limited to those with an insufficient response to medical treatment. Because of their effects on eosinophil-dominated inflammation, INSs and oral corticosteroids are the primary medical treatment strategies. The very low (≤1%) systemic bioavailability of newer INSs minimizes the systemic adverse effects seen with oral corticosteroids. Conclusion:Based on randomized, controlled trials, guidelines recommend INSs as first-line therapy for nasal polyps and for care after polypectomy. Clinical data suggest INSs are effective in reducing polyp size and relieving nasal symptoms. INS treatment has also reduced nasal polyp recurrence in patients undergoing functional endoscopic sinus surgery. Treatment with these mainstay options has been found to improve quality of life, which, along with symptom improvement, is a key factor in disease treatment.