Sinusitis is a disease that is accompanied by a runny or stuffy nose, pain in the cheeks, between the eyes, and in the head, and olfactory disturbances These symptoms can lead to a decreased quality of life due to lack of concentration and discomfort. The main cause is viral or bacterial infections, such as the common cold. Since the sinuses are connected to the nasal cavity, it is known that infection can also cause inflammation of the sinuses. When the body is invaded by a virus or bacteria, it employs highly active reactive oxygen species (ROS) to eliminate them. This causes inflammation. Therefore, ROS are elevated in areas of inflammation, resulting in increased oxidative stress. In patients with chronic sinusitis, reduced glutathione and uric acid concentrations have been reported, suggesting that chronic sinusitis is likely to play a role in oxidative stress. Twendee X is an antioxidant supplement that contains a balanced blend of eight ingredients with strong antioxidant potential. It has passed drug-level safety testing and is safe for use by both children and adults. This study reviewed the relevance of oxidative stress in sinusitis and the results of a questionnaire on symptom changes in humans with sinusitis before and after taking Twendee X. The results suggest that intervention with antioxidant supplements could improve or prevent symptoms of sinusitis.