Symptoms of nonallergic rhinitis include chronic sneezing, postnasal drip and nasal congestion in the absence of an allergenic cause, while allergic rhinitis has similar symptoms but is associated with a known allergic reaction, explains Mayo Clinic. Itchiness in the eyes, nose or throat commonly occurs with allergic rhinitis, also called hay fever, but is uncommon in patients with nonallergic rhinitis. Fatigue may also occur due to nasal obstruction causing poor-quality sleep, notes American College of Allergy, Asthma & Immunology.
There are two main categories of allergic rhinitis: seasonal and perennial, states American College of Allergy, Asthma & Immunology. Patients with seasonal allergic rhinitis experience symptoms in the presence of allergens that tend to be most prevalent during certain seasons, such as mold spores or pollen. Conversely, individuals with perennial allergic rhinitis have symptoms all throughout the year. Examples of allergens that commonly cause perennial allergic rhinitis symptoms include cockroaches, pet hair and mold.
Nonallergic rhinitis is a response to dilation of the blood vessels in the nose, causing blood and fluid to pool into the nasal lining, notes Mayo Clinic. There are numerous environmental irritants that can cause this nasal swelling, some of which include secondhand smoke, perfumes and dust. Changes in the weather, certain medications and foods, stress and hormonal fluctuations can also trigger nonallergic rhinitis.