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Allergic rhinitis

Also listed as: Hay fever; Perennial allergic rhinitis; Rhinitis - allergic; Seasonal allergies

• Signs and Symptoms
• Causes
• Risk Factors
• Diagnosis
• Preventive Care
• Treatment Approach
• Other Considerations
• Supporting Research

Allergic rhinitis is an allergic reaction to airborne particles that primarily affects the nose and eyes. There are two types of allergic rhinitis: seasonal allergic rhinitis (hay fever) and perennial allergic rhinitis, which occurs year-round. Allergens (substances that cause allergic reactions) responsible for allergic rhinitis usually enter the body by inhalation. Hay fever is caused by outdoor allergens, and perennial allergic rhinitis by indoor allergens. Symptoms of allergic rhinitis resemble a cold, except that they occur only at particular times: during certain seasons or weather patterns (hay fever), and around certain animals or small household pests (perennial allergic rhinitis). Millions of people are affected by allergic rhinitis. Many people who have allergic rhinitis also have asthma.

Signs and Symptoms

Allergic rhinitis can cause many symptoms, including the following:

• Stuffy, runny nose; discharge is generally thin and clear
• Sneezing
• Post-nasal drip
• Red, itchy, and watery eyes
• Swollen eyelids
• Itchy mouth, throat, ears, and face
• Sore throat (called pharyngitis)
• Dry cough
• Feelings of fullness and buzzing in the ears (called tinnitus)
• Headaches
• Partial loss of the senses of hearing, smell, and taste
• Fatigue
• Dark circles under the eyes

Causes

The body's immune system is designed to fight harmful substances like bacteria and viruses. But in allergic rhinitis, the immune system overresponds to substances that are harmless to most people -- like pollen, mold, and pet dander -- and launches an assault. This attack is called an allergic reaction. In an allergic reaction, substances called histamine (among other chemicals) are released. Histamines contribute to the symptoms of allergic rhinitis.

Seasonal allergic rhinitis is caused by an allergic reaction to pollens and spores (depending on the season and area) as they are carried on the wind. Sources include:

• Ragweed – the most common seasonal allergen
• Grasses
• Trees
• Fungus (mold growing on dead leaves)

Year-round allergic rhinitis is caused by an allergic reaction to airborne particles from the following:

• Animal dander (skin flakes)
• Dust and household mites
• Cockroaches
• Molds growing on wall paper, house plants, carpeting, and upholstery

Risk Factors

• Family history
• Having other allergies, such as food allergies or eczema
• Exposure to second hand cigarette smoke

Diagnosis

Your family and personal history of allergy is important in diagnosing allergic rhinitis. Questions you may be asked include the following: Do symptoms vary according to time of day or the season? Do you have a pet or are you exposed to one? Have you made changes to your diet? Are you taking any medications?

The doctor will likely examine your nose and nasal secretions. Allergy testing may reveal specific allergen(s). Skin testing is the most common method of allergy testing. This may include scratch, patch, or other tests. In a scratch test, for example, small amounts of suspected allergens are applied to the skin with a needle prick or scratch. If there is an allergy, a hive (swollen reddened area) forms within about 20 minutes. You should not take antihistamines for at least 12 to 72 hours before the test. Occasionally, the suspected allergen is dissolved and dropped onto the lower eyelid of the eye as a means of testing for allergies.

In children, observing behavior is helpful in diagnosis. Symptoms of allergic rhinitis may cause a child to wiggle the nose and push the nose upward with the palm of the hand to clear obstruction.

Preventive Care

Taking the following steps to reduce your exposure to allergens may prevent symptoms.

If you have hay fever, during days or seasons when airborne allergens are high:

• Stay indoors, and if possible, close the windows
• Use an air conditioner
• Avoid using fans that draw in air from outdoors
• Avoid air drying your clothes
• Bathe or shower and change your clothes after being outside

Pollination occurs at different times of day for different plants. For example, ragweed pollen is highest in the late morning, and grasses are highest in the afternoon. Most trees produce pollen in the spring, grasses and flowers usually produce pollen during the summer, and ragweed and other late-blooming plants produce pollen during late summer and early autumn.

If you have perennial allergic rhinitis:

• Cover your pillows and mattress with dust mite covers
• Use an air purifier
• Avoid pets and other triggers

Treatment Approach

Reducing allergy symptoms is the goal of treatment, and the best way to do this is to avoid exposure to allergens (see Preventive Care). Complete avoidance of environmental allergens may be impossible, but exposure may be minimized in many cases. For hay fever, this may be accomplished by staying indoors in air conditioned rooms on days when the count of your particular allergen is high in the environment. For perennial allergic rhinitis this means using dust mite covers for pillows and mattresses, and using an air purifier.

Drug therapies (such as antihistamines, decongestants, and nasal corticosteroid sprays) may be used to control mild to moderate symptoms and certain complementary and alternative therapies may also be used to successfully treat the symptoms of allergic rhinitis.

Desensitization (immunotherapy, or "allergy shots") is occasionally recommended. It includes regular injections of the allergen (substance causing the allergic reaction) given in increasing doses (each dose is slightly larger than the previous dose). The aim of desensitization is to gradually accustom the immune system to the allergen so that it no longer reacts to that substance. This is done very slowly and carefully, starting with minute amounts of the substance, in a controlled setting (namely, your doctor's office).

In addition to following these important treatment steps, certain lifestyle and dietary changes may help prevent or improve symptoms of allergic rhinitis. Plus, acupuncture therapy brings significant relief to many people who have allergic rhinitis as does homeopathy.

Lifestyle

Preventive measures may be taken to avoid symptoms of allergic rhinitis. Although it may be unrealistic for people with hay fever to stay indoors during all high pollen and ragweed times, other measures can reduce chances of symptoms. If possible, you should:

• Choose air conditioning over window fans
• Avoid working with compost, raking leaves, or walking through uncut fields

For perennial allergic rhinitis, you can take the following measures.

To reduce mold:

• Clean moldy surfaces. Mold is often found in air conditioners, humidifiers, dehumidifiers, swamp coolers, and refrigerator drip pans
• Reduce indoor humidity to less than 50% using air conditioners and dehumidifiers
• Fix water leaks and clean up water damage
• Put windows in or otherwise ventilate kitchens, bathrooms, and crawl spaces; vent laundry dryers to the outside
• Put flooring in crawl spaces
• Avoid carpets and upholstered furniture
• Wash bedding every week in hot water
• Keep stuffed toys out of the bedroom
• Encase pillows and beds with allergen-proof covers

Medications

Medication is recommended based on the type of allergic rhinitis. Perennial allergic rhinitis may require daily medication, and if you have seasonal allergic rhinitis (hay fever) you may be advised to start medications a few weeks before the pollen season.

Preventive Agents and Methods

• Anti-inflammatory agents— prevent severe allergic rhinitis; examples include nasal corticosteroid (steroid) sprays, leukotriene-antagonists (namely, zafirlukast and montelukast), and nasal cromolyn
• Antihistamines—relieve sneezing and itching; may prevent nasal congestion before an allergy attack; available by prescription or over-the-counter

Decongestants

Many over-the-counter and prescription decongestants are available in tablet or nasal (inhaled) form.

• Oral decongestants—commonly contain the active ingredient pseudoephedrine; side effects, such as nervousness, drowsiness, blood pressure changes, are more likely with oral than nasal decongestants
• Nasal decongestants—applied directly into the nasal passages with a spray, gel, drops, or vapors; available as long-acting (6 to 12 hours) or short-acting; work faster than oral decongestants and with fewer side effects. With extended use, nasal decongestants can cause the nasal passages to swell, and this can begin a cycle of dependency. Avoid using nasal decongestants for more than 3 days in a row, unless specifically instructed by your doctor, and avoid them altogether if you have emphysema or chronic bronchitis.

Additional Treatment for Itchy Eyes

• Antihistamine eye drops—relieve both nasal and eye symptoms; examples include azelastine, olopatadine, ketotifen, and levocabastine
• Decongestant eye drops—such as phenylephrine and naphazoline
• Combination antihistamine/decongestants

Eye drops may cause stinging or even headache.

Surgery and Other Procedures

Allergy shots (immunotherapy) are often recommended to anyone 7 years and older who has severe allergy symptoms or who also has asthma. Immunotherapy stimulates the immune system by regularly injecting minute doses of an allergen over a long period of time, causing the body to become less sensitive to the provoking substance.

Immunotherapy is generally very effective, and it has the following advantages:

• Specific allergens are targeted
• Sensitivity may be reduced in airways in the lungs as well as in the upper airways
• New allergies in children may be less likely to develop
• Asthma in children with allergies may be less likely to develop

Nutrition and Dietary Supplements

If you have any food allergies, eliminate those items from your diet. Even if you don't have any identified food allergy, reducing the intake of foods that may stimulate inflammation (such as meats, full fat dairy products, sugar, and highly processed foods) may improve your symptoms.

Bromelain

Although not all experts agree, bromelain supplements may help suppress cough, reduce nasal mucus associated with sinusitis, and relieve the swelling and inflammation caused by hay fever. This supplement is often administered with quercetin.

Essential Fatty Acids

Omega-6 fatty acids have a longstanding history of folk use for allergies. They are essential fatty acids (EFAs), meaning that they are needed by the body and must be obtained from the diet. People who are prone to allergies may require more EFAs and often have difficulty converting linoleic acid (an inflammation-provoking type of omega-6 fatty acid) to gamma-linolenic acid (GLA; an anti-inflammatory omega-6 fatty acid). In fact, women and infants who are prone to allergies appear to have lower levels of GLA in breast milk and blood. Studies on the use of EFAs to prevent allergic reactions or reduce their magnitude have had mixed results. Whether taking a GLA supplement improves your symptoms, therefore, may be very individual. Work with your healthcare provider to first determine if it is safe for you to try GLA and then follow your allergy symptoms closely for any signs of change. GLA is found in spirulina and seed oils of evening primrose, black currant, borage, and fungal oils.

In terms of dietary changes relative to EFAs, you should try to eat foods rich an omega-3 fatty acids (such as cold-water fish, flaxseeds, and walnuts). Eating foods rich in omega-3 fatty acids and limiting foods with omega-6 fatty acids (found, for example, in egg yolks, meats, and cooking oils including corn, safflower, and cottonseed,) may reduce allergy symptoms in general. This is because omega-3 fatty acids tend to decrease inflammation while omega-6 fatty acids (other than GLA) tend to increase inflammation.

Lactobacillus Acidophilus

Studies suggest that L. acidophilus , "friendly" bacteria found in the intestines, enhance the immune system. It is thought to have the potential to lower the risk of allergies, including allergic rhinitis.

N-Acetylcysteine

Cysteine is an essential amino acid found in many proteins. N-acetylecysteine (NAC), a modified form of cysteine, may reduce nasal congestion. Theoretically, therefore, taking an NAC supplement may help reduce symptoms of allergic rhinitis. This theory needs scientific study before specific recommendations can be made.

Quercetin

Quercetin is a flavonoid, a plant pigment responsible for the colors found in fruits and vegetables. Quercetin inhibits the production and release of histamine -- a substance that contributes to allergy symptoms of allergic rhinitis, such as a runny nose and watery eyes. Quercetin seems to work better when used in conjunction with bromelain, a digestive enzyme found in pineapples.

Spirulina

Test tube and animal studies suggest that spirulina, an immune system stimulant, may help protect against harmful allergic reactions. It appears that spirulina prevents the release of histamines, substances that contribute to symptoms of allergic rhinitis. Research on people is needed.

Vitamin C

Information on vitamin C for allergic rhinitis is somewhat limited, but early studies suggest that there may be a role for this vitamin in treating symptoms of hay fever and year-round allergic rhinitis.

Herbs

Herbs, like other medications, may produce side effects or interact with other medications. They should, therefore, be used with caution and only under the guidance of a professionally trained and qualified herbalist.

Butterbur ( Petasites hybridus )

Butterbur has been traditionally used to treat asthma and bronchitis and to reduce mucus. A recent study of 125 people with hay fever found that an extract of this herb was as effective and less sedating than cetirizine, a commonly prescribed non-sedating antihistamine. The study lasted only 2 weeks, and while it shows promise, it is not known what would be the effect of using butterbur over a longer time period.

Echinacea ( Echinacea angustifolia/Echinacea pallida/Echinacea purpurea )

Several test tube and animal studies suggest that echinacea contains substances that enhance the activity of the immune system and reduce inflammation. For these reasons, professional herbalists may recommend echinacea to treat allergic rhinitis. In rare cases, however, echinacea itself causes an allergic reaction. See Warnings and Precautions.

Evening Primrose ( Oenothera biennis )

This herb is considered by some to be a potential treatment for allergic rhinitis because the main active ingredient in it is gamma-linolenic acid (GLA), an essential fatty acid that may relieve allergy symptoms (see Nutrition and Dietary Supplement section).

Goldenseal ( Hydrastis canadensis )

Goldenseal is considered to be a natural antibiotic and antiseptic, and many herbalists include it in herbal remedies for allergic rhinitis. Laboratory studies suggest that berberine, the active ingredient in goldenseal, has antibacterial and immune-enhancing properties. Commercial preparations of goldenseal have very little berberine, however. Therefore, it is unclear whether it is berberine, another substance, or a combination of factors in goldenseal that may be providing the benefit reported by herbal experts.

Stinging Nettle ( Urtica dioica/Urtica urens )

Stinging nettle has traditionally been used for treating a variety of conditions, including allergic rhinitis. Studies thus far have been favorable, but not overwhelmingly so. More research is needed, but you may want to talk to your doctor about whether it is safe for you to try nettle as a possible alternative treatment.

Others

Herbs used traditionally for allergies, but with few or no studies testing their use for this purpose include:

• Astragalus ( Astragalus membranaceus )
• Devil's claw ( Harpagophytum procumbens )
• Goldenrod ( Solidago virgaurea )
• Licorice ( Glycyrrhiza glabra )

Acupuncture

Evidence suggests that acupuncture is a useful complementary or alternative treatment option for people with allergic rhinitis. In one study that included 45 people with hay fever, acupuncture was as effective as antihistamine therapy in improving symptoms and the beneficial effects appeared to last longer. Treatment for allergic rhinitis may include needling and moxibustion (a technique in which heat from the burning of an herb called mugwort [ Artemesia vulgaris ] enhances the therapeutic effect of the acupuncture needles).

Homeopathy

Although few studies have examined the effectiveness of specific homeopathic therapies, professional homeopaths may consider the following remedies for the treatment of allergic rhinitis symptoms based on their knowledge and experience. Before prescribing a remedy, homeopaths take into account a person's constitutional type. A constitutional type is defined as a person's physical, emotional, and psychological makeup. An experienced homeopath assesses all of these factors when determining the most appropriate treatment for each individual.

• Nux vomica (poison nut) -- for stuffiness with nasal discharge, dry, ticklish, and scraping nasal sensations with watery nasal discharge and a lot of sneezing; an appropriate person for this remedy is irritable and impatient
• Arsenicum album (trioxide of arsenic) -- for stuffiness with copious, burning nasal discharge and violent sneezing; an appropriate candidate for Arsenicum feels restless, anxious, and exhausted
• Allium cepa (raw onion) -- for frequent sneezing, a lot of irritating nasal discharge and tearing eyes; this person tends to feel thirsty
• Euphrasia (eyebright) -- for bland nasal discharge, with stinging, irritating tears; a suitable person for this remedy has worse nasal symptoms when lying down

Traditional Chinese Medicine

Chinese Skullcap

Chinese skullcap ( Scuterllaria baicalensis ) has been studied for its effectiveness in both animals and people. It has antioxidative, anti-inflammatory, and antihistamine properties. This makes it potentially useful for treating allergic rhinitis, particularly when used with other herbs, including stinging nettle.

Biminne

Biminne is a Chinese herbal formula used to treat allergic rhinitis. In a recent Western study of 58 people with year-round allergic rhinitis, biminne was found to effectively relieve at least some symptoms in most of the participants. Participants took the formula five times a day for 12 weeks, and they still showed the benefit of biminne even after one year. It is not known how biminne works, or if it is safe to use for extended periods.

Ephedra

Ephedra ( Ephedra sinica ), also called ma huang, has been used in Traditional Chinese Medicine for more than 5,000 years. It is used to treat nose and lung congestion. Synthetic ephedrine compounds, such as pseudoephedrine, are widely used in over-the-counter cold remedies. However, ephedra and its derivatives are potentially dangerous and addictive. Take only under the close guidance and supervision of an appropriately trained specialist.

Other Considerations

Extended use of nasal sprays can make your allergic rhinitis worse. Call your healthcare provider if you develop severe symptoms, if previously successful treatment has become ineffective, or if symptoms do not respond to treatment.

Pregnancy

If you are pregnant or breast feeding, avoid the following:

• Decongestants without discussing with your physician
• High doses of vitamin C
• Stinging nettle
• Ephedra and ephedra alkaloids such as ephedrine
• Skullcap
• Butterbur (Petasites) extracts
• Goldenseal
• Devil's claw
• Licorice

Warnings and Precautions

In rare cases, echinacea may cause allergic reactions ranging from a mild rash to anaphylaxis (a life threatening reaction accompanied by throat tightening, shortness of breath, and, possibly, loss of consciousness). People with asthma may be at an increased risk for developing these adverse reactions.

If you are allergic to ragweed, avoid other plants in the Asteraceae family (including echinacea, feverfew, asters, chamomile, and chrysanthemums).

Ephedra (ma huang) and ephedra alkaloids are associated with many side effects, some of which are very serious including irregular heart rhythm and stroke. Take only with close medical supervision.

Goldenseal should not be used over a long period of time, and it should be avoided completely if you have high blood pressure.

Skullcap has sedative properties, and should therefore be used with caution or not at all with antihistamines that make you drowsy.

Prognosis and Complications

Chances are, your symptoms of allergic rhinitis will be readily treated, but they will continue to appear with each exposure to an allergen.

Although perennial allergic rhinitis is not a serious condition, it nonetheless can interfere with many important aspects of life. Depending on the severity of your case, allergic rhinitis may be mildly disruptive to temporarily debilitating, resulting in missed days from school or work. Medication may cause drowsiness and other side effects. Your allergies could also trigger other conditions such as eczema, asthma, sinusitis, and ear infection (called otitis media). Seasonal allergic rhinitis may diminish as you age.

Desensitization may cause uncomfortable side effects (such as hives and rash) and may have dangerous side effects such as anaphylaxis. It often requires years of treatment and is effective in about two-thirds of cases.

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• Review Date: 12/1/2002
• Reviewed By: Participants in the review process include: Constance Grauds, RPh, President, Association of Natural Medicine Pharmacists, San Rafael, CA; Gary Guebert, DC, DACBR, Login Chiropractic College, Maryland Heights, MO; Jacqueline A. Hart, MD, Department of Internal Medicine, Newton-Wellesley Hospital, Boston, Ma and Senior Medical Editor A.D.A.M., Inc.; Anne McClenon, ND, Compass Family Health Center, Plymouth, MA; Marcellus Walker, MD, LAc, (Acupuncture section October 2001) St. Vincent's Catholic Medical Center, New York, NY; Ira Zunin, MD, MPH, MBA, (Acupuncture section October 2001) President and Chairman, Hawaii State Consortium for Integrative Medicine, Honolulu, HI.

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