Potential treatments for chronic rhinosinusitis include: 1. Lifestyle changes; 2. Daily nasal washing with saline; 3. Cortisone nasal sprays and pills; 4. Antibiotics; 5. Medicines containing Montelukast. 
Surgical; Your doctor will recommend surgery to clear the mucus and polyps that block the sinus cavities and reopen the sinus openings in patients who are not able to use medication due to allergy or any other reason or are not adequately controlled with drugs. Situations where surgery is beneficial include:

• When the symptoms of chronic rhinosinusitis do not improve adequately with the medical treatments mentioned above,
• In cases where the polyps are not sufficiently reduced by glucocorticoid (steroid) treatment while nasal polyps are present,
• When you have allergic fungal rhinosinusitis,
• The presence of structures that prevent the drainage of the sinuses in the paranasal sinus computed tomography,
• Severe septal deviation causing difficulty in sinus drainage or nasal congestion.

Source: http://www.kbb.org.tr