OVERVIEW
Rhinitis edit refers to inflammation of the nasal passages. This inflammation can cause a variety of annoying symptoms, including sneezing, itching, nasal congestion, runny nose, and post-nasal drip (the sensation that mucus is draining from the sinuses down the back of the throat). Brief episodes of rhinitis are usually caused by respiratory tract infections with viruses (eg, the common cold). Chronic rhinitis is usually caused by allergies, but it can also occur from overuse of certain drugs, some medical conditions, and other unidentifiable factors. For many people, rhinitis is a lifelong condition that waxes and wanes over time. Fortunately, the symptoms of rhinitis can usually be controlled with a combination of environmental measures, medications, and immunotherapy

RISK FACTORS AND CAUSES
Allergic rhinitis is caused by a nasal reaction to small airborne particles called allergens (substances that provoke an allergic reaction). In some people, these particles also cause reactions in the lungs (asthma) and eyes (allergic conjunctivitis). The allergic reaction is characterized by activation of two types of inflammatory cells, called mast cells and basophils. These cells produce inflammatory substances, such as histamine, which cause fluid to build up in the nasal tissues (congestion), itching, sneezing, and runny nose. Over several hours, these substances activate other inflammatory cells that can cause persistent symptoms. Seasonal versus perennial allergic rhinitis — Allergic rhinitis can be seasonal (occurring during specific seasons) or perennial (occurring year round). The allergens that most commonly cause seasonal allergic rhinitis include pollens from trees, grasses, and weeds, as well as spores from fungi and molds (figure 1). The allergens that most commonly cause perennial allergic rhinitis are dust mites, cockroaches, animal dander, and fungi or molds. Perennial allergic rhinitis tends to be more difficult to treat

SYMPTOMS
Nose: watery nasal discharge, blocked nasal passages, sneezing, nasal itching, post-nasal drip, loss of taste, facial pressure or pain. Eyes: itchy, red eyes, feeling of grittiness in the eyes, swelling and blueness of the skin below the eyes (called allergic shiners) (see "Patient information: Allergic conjunctivitis (Beyond the Basics)"). Throat and ears: sore throat, hoarse voice, congestion or popping of the ears, itching of the throat or ears. Sleep: mouth breathing, frequent awakening, daytime fatigue, difficulty performing work

DIAGNOSIS
The diagnosis of allergic rhinitis is based upon a physical examination and the symptoms described above. Medical tests can confirm the diagnosis and identify the offending allergens.

TREATMENT
The treatment of allergic rhinitis includes reducing exposure to allergens and other triggers, in combination with medication therapy. In most people, these measures effectively control the symptoms. Nasal irrigation and saline sprays, Nasal glucocorticoids, Antihistamines,Decongestants, Cromolyn sodium, Allergy shots.

PREVENTION
Identify allergens and other triggers and avoid them.

ADDITIONAL INFORMATION
The following organizations also provide reliable health information:
National Library of Medicine
Allergy, Asthma, and Immunology Online
American Academy of Allergy, Asthma, and Immunology

REFERENCES
1. Dykewicz MS, Fineman S, Skoner DP, et al. Diagnosis and management of rhinitis: complete guidelines of the Joint Task Force on Practice Parameters in Allergy, Asthma and Immunology. American Academy of Allergy, Asthma, and Immunology. Ann Allergy Asthma Immunol 1998; 81:478.
2.Van Cauwenberge P, Bachert C, Passalacqua G, et al. Consensus statement on the treatment of allergic rhinitis. European Academy of Allergology and Clinical Immunology. Allergy 2000; 55:116.
3. Bousquet J, Van Cauwenberge P, Khaltaev N, et al. Allergic rhinitis and its impact on asthma. J Allergy Clin Immunol 2001; 108:S147.