Rhinitis, also known as coryza, is irritation and inflammation of the mucous membrane inside the nose. Common symptoms are a stuffy nose, runny nose, sneezing, and post-nasal drip.The inflammation is caused by viruses, bacteria, irritants or allergens. The most common kind of rhinitis is allergic rhinitis, which is usually triggered by airborne allergens such as pollen and dander. Allergic rhinitis may cause additional symptoms, such as sneezing and nasal itching, coughing, headache, fatigue, malaise, and cognitive impairment. The allergens may also affect the eyes, causing watery, reddened, or itchy eyes and puffiness around the eyes. The inflammation results in the generation of large amounts of mucus, commonly producing a runny nose, as well as a stuffy nose and post-nasal drip. In the case of allergic rhinitis, the inflammation is caused by the degranulation of mast cells in the nose. When mast cells degranulate, they release histamine and other chemicals, starting an inflammatory process that can cause symptoms outside the nose, such as fatigue and malaise. In the case of infectious rhinitis, it may occasionally lead to pneumonia, either viral or bacterial. Sneezing also occurs in infectious rhinitis to expel bacteria and viruses from the respiratory tract. Rhinitis is very common. Allergic rhinitis is more common in some countries than others; in the United States, about 10–30% of adults are affected annually. Mixed rhinitis (MR) refers to patients with nonallergic rhinitis and allergic rhinitis. MR is a specific rhinitis subtype. It may represent between 50 and 70% of all AR patients.
Individuals with vasomotor rhinitis typically experience symptoms year-round, though symptoms may be exacerbated in the spring and autumn when rapid weather changes are more common. An estimated 17 million United States citizens have vasomotor rhinitis.Drinking alcohol may cause rhinitis as well as worsen asthma (see alcohol-induced respiratory reactions). In certain populations, particularly those of East Asian countries such as Japan, these reactions have a nonallergic basis. In other populations, particularly those of European descent, a genetic variant in the gene that metabolizes ethanol to acetaldehyde, ADH1B, is associated with alcohol-induced rhinitis. It is suggested that this variant metabolizes ethanol to acetaldehyde too quickly for further processing by ALDH2 and thereby leads to the accumulation of acetaldehyde and rhinitis symptoms. In these cases, alcohol-induced rhinitis may be of the mixed rhinitis type and, it seems likely, most cases of alcohol-induced rhinitis in non-Asian populations reflect true allergic response to the non-ethanol and/or contaminants in alcoholic beverages, particularly when these beverages are wines or beers. Alcohol-exacerbated rhinitis is more frequent in individuals with a history of rhinitis exacerbated by aspirin.Aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs), particularly those that inhibit cyclooxygenase 1 (COX1), can worsen rhinitis and asthma symptoms in individuals with a history of either one of these diseases. These exacerbations most often appear due to NSAID hypersensitivity reactions rather than NSAID-induced allergic reactions.The antihistamine azelastine, applied as a nasal spray, may be effective for vasomotor rhinitis. Fluticasone propionate or budesonide (both are steroids) in nostril spray form may also be used for symptomatic treatment.