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Allergic rhinitis

Hay fever; Perennial allergic rhinitis; Rhinitis - allergic; Seasonal allergies

Allergic rhinitis is an allergic reaction that happens when your immune system overreacts to substances that you inhale, such as pollen.

The two types of allergic rhinitis are:

  • Seasonal allergic rhinitis (hay fever)
  • Perennial allergic rhinitis, which occurs year-round

Hay fever is caused by outdoor allergens. Perennial allergic rhinitis is caused by indoor allergens, such as dust mites, pet dander, and mold.

Symptoms of allergic rhinitis are similar to cold symptoms. But they are not caused by a virus the way a cold is. When you breathe in an allergen, your immune system springs into action. It releases substances known as IgEs into your nasal passages, along with inflammatory chemicals, such as histamines. Your eyes may itch or your nose and sinuses may become itchy and congested. Scientists are not sure what causes your immune system to overreact to allergens.

Allergic rhinitis is common, affecting about 1 in 5 Americans. Seasonal allergic rhinitis is more common in children and adolescents. Most people with allergic rhinitis have symptoms before age 20. Symptoms stay constant through early adulthood, but begin to improve during middle age and beyond. Symptoms can be mild or severe. Many people who have allergic rhinitis also have asthma.

 

Signs and Symptoms

Allergic rhinitis can cause many symptoms, including:

  • Stuffy or runny nose
  • Sneezing
  • Post-nasal drip
  • Red, itchy, watery eyes
  • Swollen eyelids
  • Itchy mouth, throat, ears, and face
  • Sore throat
  • Dry cough
  • Headaches
  • Facial pain or pressure
  • Partial loss of hearing, smell, and taste
  • Fatigue
  • Dark circles under the eyes

Causes

The immune system is designed to fight harmful substances like bacteria and viruses. When you have allergic rhinitis, your immune system overreacts to harmless substances, like pollen, mold, and pet dander. This reaction is called an allergic reaction.

Seasonal allergic rhinitis is triggered by pollen and mold spores. Sources include:

  • Ragweed in autumn. The most common seasonal allergen.
  • Grass pollen in late spring and summer
  • Tree pollen in spring
  • Fungus, mold growing, on dead leaves, common in summer and autumn

Year-round allergic rhinitis may be triggered by:

  • Pet dander
  • Dust and household mites
  • Cockroaches
  • Molds growing on wallpaper, house plants, carpeting, and upholstery
  • Smoke
  • Smog

Risk Factors

  • Family history of allergies
  • Having other allergies, such as food allergies or eczema
  • Exposure to secondhand cigarette smoke
  • Male gender

Diagnosis

Your doctor will ask questions about your family and personal history of allergies.

  • Do symptoms change depending on the time of day or the season?
  • Do you have a pet?
  • Have you made changes to your diet?
  • Are you taking any medications?

Your doctor will do a physical exam and may also recommend a skin test to find out what you are allergic to. 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, the area will become swollen and red. Sometimes a blood test may be used to find out which allergens you react to.

With young children, it can help to watch what they do. For example, a child with allergic rhinitis may wiggle his nose and push it upward with the palm of the hand.

Prevention

The best way to control your symptoms is to avoid being exposed to the allergens that trigger them.

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

  • Stay indoors and close the windows.
  • Use an air conditioner in your home and car.
  • Avoid using fans that draw in air from outdoors.
  • DO NOT hang laundry outside to dry.
  • Bathe or shower and change your clothes after being outside.
  • Use a HEPA air filter in your bedroom.

If you have year-round allergies:

  • Cover your pillows and mattress with dust mite covers.
  • Remove carpet and install tile or hardwood floors. Use area rugs and wash them often in very hot water.
  • Use blinds instead of curtains.
  • Keep pets out of the bedroom.
  • Use a HEPA filter on your vacuum.
  • Use an air purifier.
  • Wash bedding and toys, such as stuffed animals, in very hot water once a week.

There is evidence to suggest that exposure to infections, farm animals, and even domestic pets (like cats and dogs) during infancy and early childhood may reduce the risk of developing allergic rhinitis later in life. One study even suggest that premature babies have a lower risk of allergic rhinitis because of earlier exposure to pathogens.

Treatment

The best way to reduce symptoms of allergic rhinitis is to prevent exposure to allergens.

Drugs such as antihistamines, decongestants, and nasal corticosteroid sprays may help control allergy symptoms. Some complementary and alternative therapies may also be used to treat the symptoms.

Your doctor may recommend immunotherapy, or "allergy shots." With this treatment, you receive regular injections of an allergen, with each dose being slightly larger than the previous dose. Your immune system should gradually get used to the allergen so that it no longer reacts to it.

In addition, certain lifestyle and dietary changes may help prevent or improve symptoms of allergic rhinitis.

Lifestyle

Although you cannot stay indoors during all pollen and ragweed seasons, avoiding peak exposure times can help. Use your air conditioner in your home and car, and wear a dust mask when working in the yard.

If you have year-round allergies:

  • Get rid of carpets and upholstered furniture.
  • Wash bedding every week in very hot water.
  • Keep stuffed toys out of the bedroom.
  • Cover pillows and beds with allergen-proof covers.

To reduce mold:

  • Clean moldy surfaces. Mold is often found in air conditioners, humidifiers, dehumidifiers, swamp coolers, and refrigerator drip pans.
  • Use a dehumidifier indoors to reduce humidity to less than 50%.
  • Fix water leaks and clean up water damage immediately.
  • Make sure kitchens, bathrooms, and crawl spaces have good ventilation. Installing exhaust fans can help. Vent laundry dryers to the outside.
  • Put flooring in crawl spaces.

Medications

Depending on the type of allergic rhinitis you have, your doctor may recommend medications. If you have perennial allergic rhinitis, you may need to take medication daily. If you have seasonal allergic rhinitis (hay fever) you may need to start taking your medications a few weeks before the pollen season begins.

Antihistamines

Antihistamines work by blocking the release of histamine in your body. They are available in both oral and nasal spray forms, and as prescription drugs and over-the-counter remedies. Over-the-counter antihistamines are short-acting and can relieve mild to moderate symptoms.

  • Over-the-counter antihistamines, including diphenhydramine (Benadryl), chlorpheniramine (Chlor-Trimeton), and clemastine (Tavist). These older antihistamines can cause sleepiness. Loratadine (Claritin), cetrizine (Zyrtec), and fexofenadine (Allegra) do not cause as much drowsiness as older antihistamines.
  • Prescription antihistamines, longer-acting than over-the-counter antihistamines and are usually taken once a day. They include desloratadine (Clarinex).

Decongestants

Many over-the-counter and prescription decongestants are available in pill or nasal spray form. They are often used with antihistamines.

Oral and nasal decongestants include Sudafed, Actifed, Afrin, and Neo-Synephrine. Some decongestants may contain pseudoephedrine, which can raise blood pressure. People with high blood pressure or an enlarged prostate should not take drugs containing pseudoephedrine. Using nasal decongestant sprays for more than 3 days can cause "rebound congestion," which makes congestion worse. Avoid using nasal decongestant sprays for more than 3 days in a row unless your doctor tells you to. DO NOT use them if you have emphysema or chronic bronchitis.

Nasal corticosteroids

Nasal corticosteroids are prescription sprays that reduce inflammation and help relieve sneezing, itching, and runny nose. They include:

  • Beclomethasone (Beconase)
  • Fluticasone (Flonase)
  • Mometasone (Nasonex)
  • Triacinolone (Nasacort)

It may take a few days to a week of using these sprays to see improvement in symptoms.

Leukotriene modifiers

These prescription drugs block the production of leukotrienes, which are inflammatory chemicals produced by the body. They are taken once a day and do not cause sleepiness. They are also used to treat allergic asthma. Leukotriene modifiers include montelukast (Singulair) and zafirlukast (Accolate).

Cromolyn sodium (NasalCrom)

This over-the-counter nasal spray prevents the release of histamine and helps relieve swelling and runny nose. It works best when taken before symptoms start and may needed to be used several times a day.

Nasal atropine

Ipratropium bromide (Atrovent) is a prescription nasal spray that can help relieve a very runny nose. People with glaucoma or an enlarged prostate should not use Atrovent.

Eye drops

  • Antihistamine eye drops relieve both nasal and eye symptoms. These include azelastine, olopatadine, ketotifen, and levocabastine.
  • Decongestant eye drops include phenylephrine and naphazoline.

Eye drops may cause stinging or even headache.

Other Treatments

Allergy shots or immunotherapy are often recommended to anyone 7 years and older who has severe allergy symptoms or who also has asthma. Immunotherapy helps your immune system get used to allergens through regular injections of small doses of an allergen over a long period of time.

Nasal irrigation or nasal lavage can help reduce symptoms of allergic rhinitis. One study found that doing nasal irrigation three times a day reduced allergy symptoms after about 3 to 6 weeks. To do nasal irrigation, you can use a neti pot, bulb syringe, or squeeze bottle to flush out nasal passages with salt water.

Nutrition and Dietary Supplements

Some people with allergic rhinitis also have food allergies. If you have any food allergies, eliminate those food items from your diet.

  • Lactobacillus acidophilus. One small study suggests that L. acidophilus, a type of "friendly" bacteria, might help reduce allergic reaction to pollen. More study is needed.
  • Quercetin. Quercetin is a flavonoid (plant pigment) that gives fruits and vegetables their color. In test tubes, it stops the production and release of histamine, which causes allergy symptoms such as a runny nose and watery eyes. However, there is not yet much evidence that quercetin would work the same way in humans. More studies are needed. Quercetin can potentially interfere with many medications, so speak with your physician.
  • Spirulina. Preliminary test tube and animal studies suggest that spirulina, a type of blue-green algae, may help protect against harmful allergic reactions. Spirulina stops the release of histamine, which contributes to symptoms of allergic rhinitis. Researchers don't know whether it would work in people.
  • Vitamin C (2,000 mg per day). Vitamin C has antihistamine properties and preliminary research suggests it might help reduce allergy symptoms. Other studies failed to show any effect.

Herbs

The use of herbs is a time-honored approach to strengthening the body and treating disease. However, herbs can trigger side effects and interact with other herbs, supplements, or medications. For these reasons, you should take herbs only under the supervision of a health care practitioner.

  • Butterbur (Petasites hybridus. 500 mg per day). Butterbur has been used traditionally to treat asthma and bronchitis and to reduce mucus. Several scientific studies suggest it can help with allergic rhinitis. One study of 125 people with hay fever found that an extract of butterbur was as effective as Zyrtec. Another study compared butterbur to Allegra with similar findings. However, both studies were small. So more research is needed. Researchers do not know whether taking butterbur longer than 12 to 16 weeks is safe. Butterbur can cause stomach upset, headache, and drowsiness. Pregnant and breastfeeding women, and young children, should not take butterbur. If you take any prescription medications, ask your doctor before taking butterbur. Only use butterbur products from a reputable manufacturer under the guidance of your physician. Low quality butterbur may contain potentially harmful toxins.
  • Stinging nettle (Urtica dioica, 600 mg per day for one week). Stinging nettle has been used traditionally for treating a variety of conditions, including allergic rhinitis. But studies so far are lacking. Only one small study suggested that stinging nettle might help relieve symptoms of allergic rhinitis. Pregnant women and young children should not take stinging nettle. Talk to your doctor before taking stinging nettle if you have diabetes or if you take blood pressure medication, blood thinners, diuretics, water pills, lithium, or other medications processed by the kidneys.
  • Tinospora cordifolia (300 mg three times per day). In one study, people with allergic rhinitis who took a specific formulation of tinospora (Tinofend) for 8 weeks had many fewer symptoms than those who took placebo. Some researchers questioned the results of the study. More research is needed. People who have diabetes or an autoimmune disease, such as rheumatoid arthritis or Crohn disease should not take tinospora. Pregnant or breastfeeding women should not take it, either. Tinospora can interact negatively with diabetes medications and drugs that suppress the immune system.
  • Astragalus (Astragalus membranaceus, 160 mg two times per day). One preliminary study suggested that a specific formulation of astragalus (Lectranal) standardized to contain 40% polysaccharides reduced symptoms of allergic rhinitis including runny nose, sneezing, and itching. People who have an autoimmune disease, such as rheumatoid arthritis or Crohn disease, should not take astragalus without asking their doctor. People who take lithium or drugs that suppress the immune system should not take astragalus.

Acupuncture

Some evidence suggests that acupuncture may help treat people with allergic rhinitis, although not all studies agree. In one study of 45 people with hay fever, acupuncture worked as well as antihistamines in improving symptoms and the effects seemed to last longer. However, a controlled trial that compared acupuncture to placebo (sham acupuncture) found no real benefit. One study suggested that combining acupuncture with traditional Chinese herbs did help relieve symptoms.

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, includes your physical, emotional, and psychological makeup. An experienced homeopath assesses all of these factors when determining the most appropriate treatment for each individual.

  • Nux vomica. 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. For stuffiness with copious, burning nasal discharge and violent sneezing. An appropriate candidate for Arsenicum feels restless, anxious, and exhausted.
  • Allium cepa. For frequent sneezing, a lot of irritating nasal discharge and tearing eyes. This candidate tends to feel thirsty.
  • Euphrasia. For nasal discharge, with stinging, irritating tears. A suitable person for this remedy has worse nasal symptoms when lying down.

Traditional Chinese Medicine

Biminne is a Chinese herbal formula used to treat allergic rhinitis. In a study of 58 people with year-round allergic rhinitis, biminne relieved at least some symptoms in most of the participants. People in the study took the formula 5 times a day for 12 weeks, and they still showed the benefit of biminne even after 1 year. It is not known how biminne works, or if it is safe to use for extended periods. Ask your doctor before taking it. Biminne includes these herbs:

  • Chinese skullcap (Scutellaria baicalensis). Can interact with sedatives, lithium, and diabetes medications. May also interact with statins, used to lower cholesterol.
  • Ginkgo biloba. May increase risk of bleeding and bruising. May interact with medications including blood thinners, nonsteroidal anti-inflammatory drugs (such as Advil or Aleve), and Xanax.
  • Horny goat weed (Epimedium sagittatum). May interact with blood thinners and blood pressure medications.
  • Schizandra chinensis. May interact with many medications.
  • Japanese apricot (Prunus mume). May interact with blood thinners.
  • Ledebouriella divaricata
  • Astragalus (Astragalus membranaceus). May interact with lithium and drugs that suppress the immune system.

Other Considerations

Using some nasal decongestant sprays for long periods of time can make allergic rhinitis worse. Call your doctor if you develop severe symptoms, if treatment that helped before is no longer working, or if symptoms do not get better with treatment.

Poorly controlled allergic rhinitis may lead to sleep problems, learning problems, and lost productivity at work.

Pregnancy

If you are pregnant or breastfeeding, avoid:

  • Decongestants, unless you ask your doctor
  • Stinging nettle
  • Chinese skullcap
  • Butterbur (Petasites) extracts
  • High doses of vitamin C
  • Tinospora cordifolia
  • Astragalus

Warnings and Precautions

DO NOT take stinging nettle without talking to your doctor first if you have diabetes or if you take blood pressure medication, anticoagulants (blood thinners), or diuretics (water pills).

DO NOT take tinospora cordifolia is you have diabetes or an autoimmune disease such as rheumatoid arthritis or Crohn disease.

DO NOT take astragalus if you have an autoimmune disease such as rheumatoid arthritis or Crohn disease. People who take lithium should not take astragalus.

Butterbur may interact with some medications that are processed by the liver. If you take any prescription medications, ask your doctor before taking butterbur.

Skullcap can make you sleepy and should be used with caution. DO NOT use skullcap with antihistamines that can make you drowsy.

Prognosis and Complications

You can treat symptoms of allergic rhinitis. But they will appear each time you are exposed to an allergen.

Although perennial allergic rhinitis is not a serious condition, it can interfere with your life. Depending on how severe your symptoms are, allergic rhinitis can cause you to miss 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 (otitis media). Seasonal allergies may get better as you get older.

Immunotherapy or allergy shots may cause uncomfortable side effects, such as hives and rash. Rarely, it may have dangerous side effects such as anaphylaxis. It usually works in about two-thirds of cases, and may require years of treatment.

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Review Date: 8/22/2015  

Reviewed By: Steven D. Ehrlich, NMD, Solutions Acupuncture, a private practice specializing in complementary and alternative medicine, Phoenix, AZ. Review provided by VeriMed Healthcare Network.

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