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Hay Fever

Hay fever


Hay fever, which is also called allergic rhinitis , is a common allergic condition. A main feature of the condition is an inflammation of the nasal passages, or rhinitis, caused by an allergic reaction to pollen. Hay fever usually occurs when airborne plant pollens are at their highest levels in the spring, summer, and early fall.


Hay fever is one of the most common chronic diseases in the United States. It is estimated that about 35

Runny nose
Watery eyes
Postnasal drip
Sore throat and roof of mouth
Head congestion
Ear pressure
Sleep disturbances
Nasal discharge

million people in the United States are affected. Hay fever can develop at any age, but it shows up most often in childhood through the early 20s. The term "hay fever" is not quite accurate, since the pollen of hay grasses is only one of the many possible allergens involved, and there is no fever. Although an allergy to pollen does not appear to be inherited, the tendency to allergic sensitivity in general may run in families.

Causes & symptoms

Of all the causes of allergies , pollen is one of the most widespread. Trees, weeds, and grasses produce pollen in large amounts for seed production. These pollens are dispersed by the wind, and many never reach the intended targets. Instead, they are inhaled through the nose and throat. Different plants release their pollen at different times of the year, so the timing of hay fever symptoms varies from person to person, depending on which plants provoke a response.

For people with hay fever, inhaled pollen grains are identified by the body as foreign invaders. This is probably due to a dysfunction in the immune system. The mast cells of the immune system act as storage containers for highly reactive chemical granules, including histamine. Allergens trigger a release of these granules, and the mast cells spill their chemicals into neighboring blood vessels and nerve cells. Histamine dilates the blood vessels, causing fluids to escape into surrounding tissues. This results in swelling, pooling of fluid in the tissues, and redness of the nose and eyes. Histamine also stimulates pain receptors, and causes the itchiness and discomfort of the nose, eyes, and throat that are common hay fever symptoms.

Inflammation of the nose, or rhinitis, is the major symptom of hay fever. Inflammation causes itching , sneezing, runny nose, redness, and tenderness. Swelling of the sinuses can constrict the eustachian tube that connects the inner ear to the throat, causing a feeling of congestion and popping in the ears. Mucus from the sinuses may run down the back of the throat, leading to throat irritation and redness. Seasonal fatigue and sinus headaches may also be indications of hay fever, as well as respiratory congestion and a decreased sense of smell. Severe allergies can lead to dark circles under the eyes, puffy eyelids, and creases under the eyes. Characteristically, children with hay fever may push their noses upward with the palm of their hand or twitch their noses to clear the congestion.

Virtually any type of tree or grass may cause hay fever, although plants with showy flowers usually produce a sticky pollen that is much less likely to become airborne. Among North American plants, weeds are the most prolific producers of allergenic pollen. Ragweed is the major culprit, but other plant pollens that routinely affect hay fever sufferers include sagebrush, lamb's quarter, Russian thistle, and English plantain . Grasses include timothy grass, Kentucky bluegrass, Johnson grass, Bermuda grass, redtop grass, orchard grass, and sweet vernal grass. Trees that produce allergenic pollen include oak , ash, elm, hickory, pecan, box elder , and mountain cedar.


The diagnosis of hay fever is usually simple. A thorough history of the illness is important in diagnosing allergies, including whether the symptoms vary according to time of day or the season, and possible exposures. When symptoms always appear during a particular season and disappear with the onset of cold weather, hay fever is almost certainly the culprit. For a more definitive diagnosis, a skin prick test is used, in which a diluted extract of the suspected allergen is injected superficially or scratched into the skin and the reaction is observed. Another test is a provocative challenge, which is performed by putting an extract of the suspected allergen onto the conjunctiva of the eye or in the nose or lungs. When such direct skin testing is not possible, various methods of testing the blood may be used. Other conditions causing rhinitis, such as infection, may have to be ruled out by a nasal smear, in which a sample of mucus is taken on a swab for examination.


Alternative treatments for hay fever often focus on modulation of the body's immune response. They frequently center around diet and lifestyle adjustments. A healthy diet high in fiber and whole foods, including

generous amounts of vegetables, grains, nuts, and raw seeds should be maintained. Plenty of fluids should be consumed. Six to eight glasses of water daily are recommended, along with plenty of herbal teas. Raw vegetable juices are also beneficial, particularly carrot, celery, beet, cucumber, spinach, and parsley . Meat, dairy, and foods high in saturated fats may aggravate a hay fever condition, and should be limited in the diet. It is also best to avoid dairy products, wheat, eggs, citrus fruits, chocolate, peanuts, shellfish, food colorings, and preservatives, especially sulfites. These are all common food allergens that may worsen hay fever symptoms. Caffeine , alcohol, tobacco, and sugar should be avoided, as well.

Beneficial supplements for treating hay fever include vitamins A, E, and B complex. Vitamin C , especially the buffered type, is a natural antihistamine. In substantial amounts it can help stabilize the mucous membrane response to allergens. Bioflavonoids prevent the release of histamine, and can be taken in combination with vitamin C. Essential fatty acids , contained in evening primrose oil, fish oil , or flaxseed oil, are also recommended as a daily supplement. Glutathione peroxidase is an enzyme that blocks a key inflammatory reaction in the hay fever cycle. It can play a key role in neutralizing the allergic reactions of hay fever. Selenium is a trace mineral that may help stop the inflammation due to allergens and reduce other allergy symptoms.

For symptom relief, nettles (Urtica dioica ) have been reported to have the ability to clear the sinuses and to greatly reduce other symptoms. Tincture of licorice (Glycerrhiza glabra ) is also recommended. A good tincture combination for hay fever is comprised of equal parts of black cohosh (Cimicifuga racemosa ), Chinese skullcap (Scutellaria baicalensis ), pleurisy root, orbutterflyweed (Asclepias tuberosa ), catnip (Nepeta cataria ), and cayenne pepper (Capsicum frutescens ). Other western herbal remedies herbs found to be effective include ginger root (Zingiber officinale ), eyebright (Euphrasia officinalis ), goldenseal (Hydrastis canadensis ), ephedra, horseradish (Amoracia rusticana ), and mullein (Verbascum thapsus ). Bee pollen may also be effective in alleviating or eliminating hay fever symptoms. Bee pollen should be taken a few months before the hay fever season starts. It desensitizes the body and can dramatically reduce hay fever symptoms.

Acute attacks of hay fever often respond to homeopathic remedies. Possible hay fever remedies include Allium cepa, Arsenicum album , euphrasia, Ferrum

phosphoricum, gelsemium, Natrum muriaticum, Nux vomica , sabadilla, and wyethia, depending on the associated symptoms. Since hay fever is often associated with deep-seated health problems, it is often best addressed with a constitutional remedy and the guidance of an experienced homeopathic practitioner.

Indoor allergens can cause increased sensitivity to outdoor allergens. Therefore allergy testing for allergens other than pollen should be done, and those allergens should be removed from the diet or the environment to the greatest extent possible.

Allopathic treatment

The goal of most medical approaches to hay fever treatment is reduction of symptoms. Avoidance of the allergens is best, but this is often not possible. When it is not possible, drug therapy is the major form of medical treatment used. Care should be taken, however, since a wide variety of antihistamines are available, and they all have potential side effects that impact function. These may include drowsiness, heart problems, and harmful interactions with other medications and medical conditions. The extended use of topical decongestants can cause rebound congestion that is worse than the original problem.

Antihistamines block the action of histamine. They are most effective when used preventively, before symptoms appear. Over-the-counter antihistamines are often sufficient to provide relief for hay fever symptoms. People with severe or frequent symptoms, however, may need stronger, prescription antihistamines. Azelastine, an antihistamine nasal spray, is effective and causes fewer side effects than oral antihistamines. When antihistamines do not relieve nasal symptoms, a nasal spray of cromolyn sodium is sometimes used. It works by preventing the release of histamine and similar chemicals.

Decongestants constrict blood vessels and counteract the effects of histamine. They may also be helpful in reducing symptoms such as nasal congestion. Nasal sprays are available that can be applied directly inside the nose. Oral decongestants are available as well. Phenyl-propanolamine, phenylephrine, or pseudoephedrine are available in many preparations combined with antihistamines to increase the effectiveness of the drugs. Decongestants are stimulants and may cause increased heart rate and blood pressure, headaches, and agitation.

Corticosteroids may be prescribed to reduce severe symptoms. An intranasal corticosteroid spray can be quite useful in reducing inflammation of the mucous membranes. Severe symptoms that do not respond to other treatment may require a course of oral corticosteroids. Corticosteroids are best started before allergy season begins. They are especially effective because they work more slowly and last longer than most other types of medication.

Late in 2001, researchers reported the first of many new drugs that may change treatment of hay fever and asthma : omalizumab. A monoclonal antibody, omalizumab works by blocking immunoglobulin E (IgE), an antibody produced in excessive amounts in people suffering from hay fever.

Expected results

It is possible that hay fever can be outgrown if the immune system becomes less sensitive to the pollen. However, while hay fever may improve over time, it may also get worse or even lead to the development of new allergies. Hay fever treatment may sometimes cause uncomfortable and even dangerous side effects. However, most people can achieve acceptable hay fever relief with a combination of preventive strategies and treatment.


There is no known way to prevent development of hay fever, but subsequent attacks may be reduced or prevented. Immunotherapy, also known as desensitization or allergy shots, involves injections of very small but gradually increasing amounts of an allergen over several weeks or months, with periodic boosters. This serves to acclimatize, or familiarize, the body to encountering the allergen without having a major allergic response. Individuals receiving allergy shots will be monitored closely following each shot because of the small risk of anaphylaxis. Full benefits of the shots may take up to several years to achieve, and even then about one person in five does not receive any benefit from the immunotherapy.

Reducing exposure to pollen may reduce symptoms of hay fever. Most trees produce pollen in the spring, while most grasses and flowers produce pollen during the summer, and ragweed and other late-blooming plants produce pollen during late summer and early autumn. People with hay fever should be aware of their particular "pollen season" and remain indoors whenever possible during that time. A pollen count can be used as a general guide for when it is most advisable to stay indoors to avoid contact with the pollen. Unfortunately, moving to a region with consistently low pollen counts is rarely effective, since new allergies often develop to the local flora.

Further strategies to prevent or reduce hay fever attacks include the following:

  • Remain indoors with windows closed during the morning hours, when pollen levels are highest.
  • Car windows should be kept rolled up while driving.
  • A surgical facemask can be worn when outside.
  • Forests and fields of grasses should be avoided, especially at the height of the pollen season.
  • Clothes and hair should be washed after being outside.
  • Air conditioners or air filters should be used in the home, and their filters should be changed regularly.



Adelman, Daniel C., et al., eds. Manual of Allergy and Immunology. 4th ed. Boston: Little, Brown & Co., 2002.

Weil, Andrew. Natural Health, Natural Medicine: A Comprehensive Manual for Wellness and Self-Care. New York: Houghton Mifflin Co., 1995.


Plaut, Marshall. "Immune-Based, Targeted Therapy for Allergic Diseases." JAMA, The Journal of the American Medical Association. (December 19, 2001): 3005.

OTHER Medical Encyclopedia. "Allergic rhinitis." [cited October 2002]. <>.

Merck & Co., Inc. "Disorders with Type I Hypersensitivity Reactions." [cited October 2002]. <>.

Virtual Hospital of University of Iowa Health Care. [cited October 2002]. <>.

Patience Paradox

Teresa G. Odle

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hay fever

hay fever, seasonal allergy causing inflammation of the mucous membranes of the nose and eyes. It is characterized by itching about the eyes and nose, sneezing, a profuse watery nasal discharge, and tearing of the eyes. The cause is a sensitivity to one or more species of pollens or fungi. In addition, many patients with hay fever develop other allergic conditions, e.g., asthma and sinusitis. In the spring, hay fever may be caused by tree pollens (oak, elm, maple); in summer, by grass pollens, wheat or corn rusts, or fungus spores; in late summer and fall, by ragweed pollen, which is the most common cause. Temporary relief of symptoms may be obtained from antihistamines and decongestants, such as ephedrine. Physicians may resort to corticosteroids in severe cases. Sometimes desensitization measures are taken, consisting of repeated injections of small amounts of the allergen (pollen) until its presence produces no symptoms; however, the treatment must be continued from year to year, since immunity is not permanent. Some relief can be obtained by removing pollen from the air by air conditioners and filters.

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Hay Fever



Hay fever is an inflammation of the nasal passages. It is an allergic reaction to substances present in the air. The medical name for hay fever is allergic rhinitis (pronounced ri-NI-tuss).


Hay fever is the most common allergic condition (see allergies entry). An allergic condition is a reaction by the body to some substance that is harmless to most people. For example, most people are not bothered by dust in the air. For other people, however, inhaling dust can cause dramatic bodily changes, such as sneezing, coughing, and itchy and watery eyes.

Between 10 and 20 percent of all people in the United States have hay fever. The condition accounts for about 2 percent of all visits to doctors. The drugs used to treat hay fever make up a significant fraction of both prescription and over-the-counter drug sales each year.

There are two types of hay fever: seasonal and perennial. Seasonal hay fever occurs in the spring, summer, and early fall. During these seasons, the level of plant pollens in the air is at its highest. Perennial hay fever occurs all year. It is usually caused by substances found in the air at home or in the workplace. A person may have one or both types of hay fever. Symptoms of seasonal hay fever are worst after being outdoors. Symptoms of perennial hay fever are worst after spending time indoors. Both forms of hay fever can develop at any age. In most cases, they first appear during childhood. They may become either worse or better over time.


Hay fever is a kind of immune reaction. The immune system consists of cells, tissues, and molecules whose job it is to fight off foreign invaders, such as bacteria and viruses. When a foreign substance enters the body, the immune system releases antibodies. Antibodies are chemicals with the ability to destroy the foreign substances.

In the case of hay fever, the immune system becomes confused. It treats dust, pollen, and other harmless substances as if they were dangerous invaders. Substances that cause this kind of reaction are known as allergens. The immune system releases antibodies against allergens the way it does against bacteria, viruses, and other dangerous substances.

The combination of antibody and allergen sets off a series of reactions designed to protect the body. These reactions cause cells and blood vessels to leak fluids. These fluids cause the familiar symptoms of hay fever, such as a runny nose, red and irritated eyes, an itchy nose, and a scratchy throat.

Hay Fever: Words to Know

A substance that provokes an allergic response.
Increased sensitivity caused by previous exposure to an allergen that can result in blood vessel dilation (swelling) and smooth muscle contraction. Anaphylaxis can result in sharp blood pressure drops and difficulty breathing.
A specific protein produced by the immune system in response to a specific foreign protein or particle called an antigen.
Small packets of reactive chemicals stored within cells.
A chemical released by mast cells that activates pain receptors and causes cells to that leak fluids.
Mast Cells:
A type of immune system cell that is found in the lining of the nasal passages and eyelids. It displays a type of antibody called immunoglobulin type E (IgE) on its cell surface and participates in the allergic response by releasing histamine from intracellular granules.

The number of possible allergens found in the air is enormous. Seasonal hay fever is most commonly caused by grass and tree pollen. Pollen is a fine powder by which plants are germinated. A number of weeds can also cause hay fever. These include:

  • Ragweed
  • Sagebrush
  • Lamb's quarters
  • Plantain
  • Pigweed
  • Dock (sorrel)
  • Tumbleweed

Perennial hay fever is also caused by a variety of particles found in the air including:

  • Body parts of house mites. House mites are tiny insects. They can be seen only with the aid of a microscope. They feed on fibers, fur, and skin shed by people who live in the house. When they die, their body parts get into the air.
  • Animal wastes. Animals constantly shed fur, skin flakes, and dried saliva. Common sources of these materials are pet dogs, cats, and birds. These materials easily get into the air. They cause allergic reactions in many people.
  • Mold spores. Mold is a fungus that grows in warm, damp places. It lives in basements, bathrooms, air ducts, air conditioners, refrigerator drains, mattresses, and stuffed furniture. Mold reproduces by giving off tiny seed-like particles called spores. These spores are released into the air. They can cause hay fever in many people.

Other possible causes of perennial hay fever include the following:

  • Cigarette smoke
  • Perfume
  • Cosmetics
  • Cleansers
  • Chemicals used in copy machines
  • Industrial chemicals
  • Gases given off by construction materials, such as insulation


Common symptoms of hay fever include a tender, itchy, runny nose, accompanied by sneezing and coughing. The sinuses may also begin to swell, causing the eustachian (pronounced you-STAY-shee-un) tube to close up. The eustachian tube connects the inner ear to the throat. The closing of the eustachian tube causes a feeling of stuffiness. Mucus may drip from the sinuses into the throat, causing the throat to become sore. Hay fever may also cause red, itchy, watery eyes. Fatigue and headache are also common.


Hay fever can usually be diagnosed quite easily. Symptoms and a medical history usually indicate the presence of the condition. When symptoms appear in the spring and disappear in the fall, seasonal hay fever is likely to be the cause. Perennial hay fever can often be diagnosed by asking the patient what substances seem to cause his or her symptoms.

Skin tests are often used in diagnosing hay fever. The first step in conducting a skin test is to place a small amount of a suspected allergen on the skin. The doctor then scratches the skin very lightly. The scratch allows the allergen to get into the bloodstream. After a few minutes, the doctor checks the area being tested. A redness and swelling indicate that the patient is allergic to the material being tested. In most cases, twenty or more materials can be tested at one time. The tests are carried out on the patient's back or forearm.


The best treatment for hay fever is to avoid the allergens that cause the condition. For example, people who are allergic to grass should not mow the lawn. It may be difficult to avoid allergens, however. In that case, two other treatments are available: drugs and immunotherapy.


Some types of drugs used to treat hay fever include the following:

  • Antihistamines. Antihistamines block the action of histamine (pronounced HISS-tuh-meen) in the immune system. Histamine is a chemical that causes many of the symptoms of hay fever. Antihistamines can be used after the symptoms of hay fever appear, but they are more effective if used before the symptoms appear. Many older types of antihistamines caused drowsiness. Some newer types do not have this side effect.
  • Decongestants. Decongestants constrict (shrink) blood vessels. They reduce the loss of fluid from blood vessels that causes many symptoms of hay fever. Decongestants are sold as pills and as nasal (nose) sprays. One dangerous side effect is that they increase blood pressure and heart rate. They should not be taken for more than a few days at a time.
  • Topical corticosteroids. Topical corticosteroids (pronounced kor-tih-ko-STIHR-oids) reduce inflammation and swelling of tissue. They tend to work more slowly and last longer than other forms of medication. As a result, they should be started before the hay fever season begins.
  • Mast cell stabilizers. Mast cells are cells produced by the immune system. They are responsible for the early stages of an allergic reaction. Mast cell stabilizers stop the allergic reaction before it gets started. They can also be used before the hay fever season begins. In that case, they reduce the chance that hay fever will develop.


Immunotherapy is also known as desensitization or allergy shots. The principle behind immunotherapy is to get the immune system more familiar with an allergen. The procedure consists of a series of injections of the allergen to which the patient is allergic. The first few shots contain a very small amount of the allergen. Over time, the shots contain slightly more allergen

each time. With each shot, the immune system becomes more familiar with the allergen. It produces a more limited reaction to the material. Eventually, the injections contain as much allergen as a patient is likely to encounter in daily life. At that point, the immune system may no longer react to the allergen.

Immunotherapy may take many weeks, months, or even years to achieve this goal. Sometimes the procedure does not work at all. One serious side effect of immunotherapy is anaphylaxis (pronounced a-neh-feh-LAK-siss). Anaphylaxis is characterized by a sharp drop in blood pressure and difficulty with breathing. A person can go into anaphylactic shock and die very quickly. For this reason, the person giving an allergy shot must watch the patient very closely for any unexpected responses.

Alternative Treatment

Some alternative practitioners believe that hay fever should be treated by strengthening the immune system. They may recommend a more balanced diet and changes in one's lifestyle. Vitamin C is sometimes recommended to reduce inflammation of tissues. Some herbs that are recommended for relief of hay fever symptoms include eyebright, bee pollen, and nettle.


Hay fever can usually be kept under control. By avoiding allergens, taking medications, and using immunotherapy, a person can reduce or eliminate most symptoms. In some cases, allergic reactions become worse over time. In other cases, they improve.


There are many things a person can do to avoid allergic reactions. Some of the most common recommendations for preventing seasonal hay fever include:

  • Stay indoors with windows closed during the morning hours, when pollen levels are highest.
  • Keep car windows closed while driving.
  • Wear a surgical mask when it is necessary to be outdoors.
  • Avoid trees, bushes, flowers, and other plants to which one is allergic.
  • Wash clothes and hair after being outside.
  • Clean air conditioner filters in the home regularly.
  • In severe cases, consider moving to an area with fewer allergens.

To reduce the symptoms of perennial hay fever, one needs to avoid mold spores, house dust, and animal wastes by taking steps such as the following:

  • Keep the house dry through ventilation and use of dehumidifiers.
  • Keep bathroom floors and walls clean with a disinfectant.
  • Clean and disinfect air conditioners and coolers.
  • Throw out moldy or mildewed books, shoes, pillows, and furniture.
  • Vacuum frequently and change the vacuum bag regularly.
  • Clean floors and walls with a damp mop.
  • Avoid contact with pets to which one is allergic.
  • Wash hands after contact with pets and other animals.
  • Keep pets out of the bedroom, and off furniture and other areas where their waste materials may collect.
  • Have pets bathed and groomed regularly.



Jelks, Mary. Allergy Plants: That Cause Sneezing and Wheezing. Tampa, FL: World-Wide Publications, 1994.

Novick, N. L. You Can Do Something about Your Allergies. New York: Macmillan, 1994.

Sussman, Les. Relief from Hay Fever and Other Airborne Allergies. New York: Dell Books, 1992.


American Academy of Allergy, Asthma, and Immunology. (800) 8222762.

Asthma and Allergy Foundation of America. 1125 15th Street, NW, Suite 502, Washington, DC 20005. 8007ASTHMA.

National Institute of Allery and Infectious Diseases. Building 31, Room 7A-50, 31 Center Drive, MSC 2520, Bethesda, MD 20892-2520.

Web sites

"Allergies." [Online] (accessed on October 21, 1999).

The On-Line Allergy Center. [Online] (accessed on October 21, 1999).

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hay fever

hay fever (hay) n. a form of allergy due to pollen, characterized by inflammation of the membrane lining the nose and sometimes of the conjunctiva (vernal or allergic conjunctivitis). The symptoms of sneezing, running or blocked nose, and watering eyes often respond to treatment with antihistamines. Medical name: allergic rhinitis.

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hay fever

hay fe·ver • n. an allergy caused by pollen or dust in which the mucous membranes of the eyes and nose are itchy and inflamed, causing a runny nose and watery eyes.

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hay fever

hay fever Seasonal allergy induced by grass pollens. Symptoms include asthma, itching of the nose and eyes, and sneezing. Symptoms are controlled with an antihistamine.

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