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Rhinitis is inflammation and swelling of the mucous membrane of the nose, characterized by a runny nose and stuffiness and usually caused by the common cold (see Viral Infections: Common Cold) or an allergy (see Allergic Reactions and Other Hypersensitivity Disorders: Seasonal Allergies).
The nose is the most commonly infected part of the upper airways. Rhinitis may be acute (short-lived) or chronic (long-standing). Acute rhinitis commonly results from viral infections but may also be a result of allergies or other causes. Chronic rhinitis usually occurs with chronic sinusitis (chronic rhinosinusitis).
Acute viral rhinitis:
Acute viral rhinitis (the common cold) can be caused by a variety of viruses. Symptoms consist of runny nose, sneezing, congestion, postnasal drip, cough, and a low-grade fever. Stuffiness can be relieved by taking decongestants such as oxymetazoline or phenylephrine as a nasal spray or pseudoephedrine by mouth. These drugs, available over the counter, cause the blood vessels of the nasal mucous membrane to narrow (constrict). Nasal sprays should be used for only 3 or 4 days because after that period of time, when the effects of the drugs wear off, the mucous membrane often swells even more than before. This phenomenon is called rebound congestion. Antihistamines help control runny nose but cause drowsiness and other problems, especially in older people (see Aging and Drugs: Some Drugs Particularly Likely to Cause Problems in Older People ). Antibiotics are not effective for acute viral rhinitis.
Allergic rhinitis:
Allergic rhinitis is caused by a reaction of the body's immune system to an environmental trigger. The most common environmental triggers include dust, molds, pollens, grasses, trees, and animals. Symptoms include itching, sneezing, runny nose, stuffiness, and itchy, watery eyes. A doctor may diagnose allergic rhinitis based on a person's history of symptoms. Often, the person has a family history of allergies. More detailed information may be obtained from blood tests or skin testing.
Avoiding the substance that triggers the allergy prevents symptoms but is often not possible. Nasal corticosteroid sprays decrease nasal inflammation caused by many sources and are relatively safe for long-term use. Antihistamines help prevent the allergic reaction and thus symptoms. Antihistamines dry the mucous membrane of the nose but many of them also cause sleepiness and other problems, especially in older people. Newer ones require a prescription but do not have these side effects. Allergy shots (desensitization) help to build long-term tolerance to specific environmental triggers, but they may take months or years to become fully effective. Antibiotics do not relieve the symptoms of allergic rhinitis.
Chronic rhinitis:
Chronic rhinitis is usually an extension of rhinitis caused by inflammation or a viral infection. However, it also may rarely occur with diseases such as syphilis, tuberculosis, rhinoscleroma (a skin disease characterized by very hard, flattened tissues that first appear on the nose), rhinosporidiosis (an infection in the nose characterized by bleeding polyps), leishmaniasis, blastomycosis, histoplasmosis, and leprosy—all of which are characterized by the formation of inflamed lesions (granulomas) and the destruction of soft tissue, cartilage, and bone. Chronic rhinitis causes nasal obstruction, pus-filled discharge from the nose, and frequent bleeding.
Both low humidity and airborne irritants can result in chronic rhinitis. Decongestants may relieve symptoms. Any underlying bacterial infection requires a culture (examination of microorganisms grown from a sample of mucus to identify infection with bacteria or fungi) or biopsy (removal of a tissue sample for identification under a microscope) and appropriate treatment.
Atrophic rhinitis:
Atrophic rhinitis is a form of chronic rhinitis in which the mucous membrane thins (atrophies) and hardens, causing the nasal passages to widen (dilate) and dry out. This atrophy often occurs in older people. The cells normally found in the mucous membrane of the nose—cells that secrete mucus and have hairlike projections to move dirt particles out—are replaced by cells like those normally found in the skin. The disorder can develop in someone who had sinus surgery in which a significant amount of intranasal structures and mucous membranes were removed. A prolonged bacterial infection of the lining of the nose is also a factor.
Crusts form inside the nose, and an offensive odor develops. People may have recurring severe nosebleeds and can lose their sense of smell (anosmia).
Treatment is aimed at reducing the crusting, eliminating the odor, and reducing infections. Topical antibiotics, such as bacitracin applied inside the nose, kill bacteria. Estrogens and vitamins A and D sprayed into the nose or taken by mouth may reduce crusting by promoting mucosal secretions.
Vasomotor rhinitis:
Vasomotor rhinitis is a form of chronic rhinitis. Nasal stuffiness, sneezing, and a runny nose—common allergic symptoms—occur when allergies do not seem to be present. In some people, the nose reacts strongly to irritants (such as dust and pollen), perfumes, and pollution. The disorder comes and goes but is worsened by dry air. The swollen mucous membrane varies from bright red to purple. Sometimes, people also have slight inflammation of the sinuses. If inflammation of the sinus is not severe, treatment is aimed at relieving symptoms. Avoiding smoke and irritants and using a humidified central heating system or vaporizer to increase humidity may be beneficial. Nasal corticosteroid sprays sometimes help. Nasal decongestant sprays should not be used. However, decongestants taken by mouth may be used for a few days at a time when symptoms are worst.
Last full review/revision October 2012 by Marvin P. Fried, MD
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