What is rhinitis?

Causes and Symptoms

Rhinitis can have a variety of causes, including infection by a rhinovirus or certain bacteria and exposure to cold air or nasal allergens. Foreign bodies in the nose and certain structural deformities can also cause rhinitis.

When the nasal symptoms are due to allergies, the condition is called allergic rhinitis. A partial list of allergens that can produce allergic rhinitis includes pollen, dust, molds, wool, feathers, tobacco smoke, airborne environmental pollutants, strong odors, spicy foods, and animal dander.

When the nasal symptoms are not due to allergies, the condition is called nonallergic rhinitis or nonallergic vasomotor rhinitis. Nonallergic rhinitis can be caused by a viral or bacterial infection, exposure to cold air, structural deformities, certain endocrine disorders such as hypothyroidism, or emotional stress; it is occasionally observed during the first trimester of pregnancy. Nonallergic rhinitis usually begins with a feeling of irritation in the nose or throat. The irritation is followed by sneezing and mucus discharge as the nasal air passageways become more obstructed.

Atrophic rhinitis, a chronic form of nonallergic rhinitis, is a condition often seen first at puberty; because there is a genetic component, the condition tends to run in families. The causes of atrophic rhinitis are not fully understood, although deficiencies in iron and vitamins A and D may contribute. In this condition, the moist, pink, thick lining of the inside of the nose is replaced by a thin crusty surface that can be foul smelling. Although the nasal cavity is wide open, people often complain of a feeling of stuffiness. The condition is sometimes accompanied by nosebleeds.

Nasal dripping and/or sneezing can be seen with all the forms of rhinitis. The discharge can be clear and watery or thicker and more viscous. It can be colorless; if there is a color, it is often white or less often green or yellow. Postnasal drip is when the discharge is into the back of the throat, a condition that can result in a dry, usually nonproductive cough.

Treatment and Therapy

The treatment for rhinitis is an attempt to manage symptoms. The most effective treatment for allergic rhinitis is to remove the source of the irritation. In the home, keeping the windows closed, using an air conditioner, and filtering the circulating air can reduce allergen exposure. Saline irrigation can also be used to reduce the nasal symptoms. When symptoms persist despite these efforts, treatment focuses on minimizing the allergic response. This can be done using antihistamines, steroids, or antileukotrienes.

When the body encounters an allergen, the white blood cells produce antibodies, which then promote the release of compounds called mediators. Histamine is perhaps the best known of these mediators. The mediators trigger the nasal symptoms. Most of the drugs used to treat allergic rhinitis are designed to inhibit the actions of the mediators. Antihistamines block the action of histamine and so significantly reduce swelling and discharge. Likewise, antileukotrienes work by blocking leukotrienes, another immune system mediator. The mechanism by which nasal steroids (usually given in the form of a spray) work is less clear, but they can provide temporary relief.

When the symptoms do not respond well to the above treatments, immunotherapy is required. For this treatment, it is necessary to determine the allergens to which the person is sensitive. This can be accomplished in a variety of ways, although skin or blood testing are the most common. Once the specific allergen has been identified, the immune system can be desensitized through carefully administered challenges, which in effect raise the tolerance level necessary to produce the nasal symptoms.

If the cause of nonallergic rhinitis was exposure to cold air, then going into a warmer environment will usually eliminate the symptoms. If the cause is the common cold or the flu, then symptoms are sometimes relieved by decongestants and/or antihistamines. Some of these drugs are available over the counter, while others require a prescription. Unless there is a primary or secondary bacterial infection accompanying the rhinitis, antibiotics are not effective. Drinking lots of fluids, getting bed rest, and breathing humidified air can reduce the discomfort. With any viral or bacterial infection (especially H1N1 influenza infections), a medical professional should be consulted immediately if breathing becomes a problem. Muscle aching and the general feeling of malaise that accompanies nonallergic rhinitis can often be relieved by over-the-counter medications such as aspirin or ibuprofen.

Atrophic rhinitis can be treated be irrigating the nose with saline. If a bacterial infection is present, then antibiotics are indicated. The crusting can be treated by irrigation with nasal douches. In severe cases, atrophic rhinitis is treated by Young’s operation, a surgical procedure that reduces the size of the nasal cavity.

When the cause of the rhinitis is a foreign body or structural deformity, removing the foreign body or surgically changing the internal structure of the nose often eliminates the symptoms.

Perspective and Prospects

Considerable financial and personal costs are associated with rhinitis, since it is such a common condition. Because rhinitis is so common, considerable effort is going into completely understanding this disease. As a result, new treatments with fewer side effects should become available.

Bibliography

Baraniuk, James N., and Dennis Shusterman, eds. Nonallergic Rhinitis. New York: Informa Healthcare, 2007.

Busse, William W., and Stephen T. Holgate, eds. Asthma and Rhinitis. Hoboken, N.J.: Wiley-Blackwell, 2000.

Carson-DeWitt, Rosalyn. "Allergic Rhinitis." Health Library, October 31, 2012.

Henochowicz, Stuart I. "Allergic Rhinitis." MedlinePlus, June 17, 2012.

Henochowicz, Stuart I. "Vasomotor Rhinitis." MedlinePlus, June 17, 2012.

Scadding, Glenis K., and Wytske J. Hokkens. Rhinitis. Albuquerque, N.Mex.: Health Press, 2007.