Chronic sinusitis is one of the most common presenting complaints of all doctor visits in the United States and Europe, with more than 13% of people affected in any given year. This disease has a wide range of impact on communities. Patients with recurrent or chronic sinusitis report a deteriorative sense of general health and vitality, when compared to general population. In our Department we perform about 600 functional endoscopic sinus surgeries (FESS) per year. Chronic rhinosinusitis represents a spectrum of inflammatory and infectious processes concurrently affecting the nose and paranasal sinuses. Among chronic paranasal sinusitis one must single out paranasal sinusitis with and without polyps. In the paranasal sinusitis patomechanism the blockage of natural ostium plays one of the most important roles. The closure of sinus proper ventilation passages leads to the triggering of many pathological occurrences within mucous membrane of this region. The treatment of paranasal sinusitis is diversified and involves a surgical procedure as well as anti-inflammatory and antiallergic drugs (medications) and mucolytics. Its purpose is to clear the nose through the elimination of bacterial infection, liquidating and removal of lying discharge and the restoration of the proper muco-ciliary transportation, and through this the improvement of local condition and faster recovery. In this work the usage of carboxycysteine to treat paranasal sinus conditions has been presented.