Have you experienced coughing, sneezing, itchy or running nose and eyes during certain times of the year? If so, you may suffer from seasonal allergies. Chronic sinusitis, however, is a more serious condition and is oftentimes mistaken by patients for seasonal allergies. Different factors that can cause chronic sinusitis include allergies, nasal polyps, asthma and in various cases, something making it difficult for your body to fight infection.How can you tell if you're experiencing seasonal allergies or something more serious?Chris Brook, MD discusses sinusitis and sinus headache, and how to tell if you need to see a specialist for treatment.