Medical therapy and smell dysfunction.

Olfactory dysfunction is deemed to be a significant contributor to poor quality of life in different nasal inflammatory conditions like common cold, allergic rhinitis, and acute and chronic rhinosinusitis with and without nasal polyps (NP). The mechanism underlying olfactory impairment in inflammatory sinonasal disease relates to either the obstruction of the olfactory cleft due to congestion of the nasal mucosa, the presence of secretions or polyps inside the nasal cavity, or to dysfunction of the sensory mucosa of the olfactory bulb resulting from local inflammation. The reduction of smell capacity in nasal inflammatory conditions may have an acute or gradual onset, often with resolution of smell dysfunction after adequate medical treatment or surgery. In contrast to the well documented effects of surgery for rhinosinusitis on smell dysfunction, the available information about the effects of medical treatment is limited. Most studies have looked at corticosteroids, evaluating the restoration of olfactory capacity as a primary or secondary study outcome parameter. Both nasal and systemic corticosteroids have a beneficial effect on olfactory dysfunction, with systemic treatment being the most powerful. This review aims to provide an overview of current knowledge about medical treatment for rhinosinusitis and its effects on smell.