Hay Fever , The Patient Education Institute, Inc. imf30101 Last reviewed: 06/27/2013 1

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1 Hay Fever Introduction Hay fever is another name for a pollen allergy. Trees, weeds and grasses release tiny pollen grains into the air. When pollen gets into your nose and throat, it can cause an allergic reaction commonly known as hay fever. Hay fever can cause sneezing, coughing and itchy eyes, nose and throat. It can also cause dark circles to form under your eyes. But treatments are available for both immediate and long-term relief. This reference summary will help you understand the causes, symptoms and treatment of hay fever. Information about the diagnosis and prevention of hay fever is also included. Hay Fever Of all the things that can cause an allergy, pollen is one of the most common. Hay fever is an allergic reaction to pollen. It is very common. Hay fever does not mean you are allergic to hay. In fact, hay fever is almost never triggered by hay. It also does not cause a fever. A better term to describe the real cause of hay fever is pollen allergy. Although many people refer to a pollen allergy as hay fever, health experts usually refer to it as seasonal allergic rhinitis. It is an allergy to pollen that causes a runny or clogged nose during certain seasons. The people most at risk for developing hay fever are people with other allergies or asthma. If you have a blood relative such as a parent or sibling with allergies or asthma, you have a greater risk of developing hay fever. Being regularly exposed to allergens also raises your risk of developing hay fever. This may be the case if you live or work in an area with large amounts of pollen in the air. 1

2 Symptoms Hay fever can cause symptoms that range from mild to life threatening. Severe allergic reactions can cause death. Hay fever can be fatal if it is severe enough to cause a life threatening reaction to an allergen. This type of reaction is called anaphylaxis. For people with extremely severe hay fever, the body may react to pollen by blocking the airway and making it hard or impossible for a person to breathe. A person cannot tell how severe his or her next allergic reaction will be based on the severity of previous reactions. Many of the cells that protect the body from harmful substances are found in the nose, throat, lungs, skin and gastrointestinal, or GI, tract. These areas are often affected by an allergic reaction. Common symptoms of hay fever include: Cough. Itching in the mouth or swelling. Itchy eyes. Red and watery eyes. Runny or stuffy nose. Sneezing. Hay fever can also cause more severe symptoms, such as: GI symptoms, such as vomiting, diarrhea or abdominal cramps and pain. Hives or eczema. Tightening of the throat and trouble breathing. Anaphylaxis and death. Other severe symptoms include the feeling that something bad is going to happen, pale skin caused by low blood pressure or loss of consciousness. Causes Each spring, summer and fall, tiny pollen grains are released from trees, weeds and grasses. The wind carries these grains through the air. When it is in the air, pollen can enter your eyes, nose and throat. In people with hay fever, this causes an allergic reaction. 2

3 The body s immune system fights viruses and bacteria that can harm the body. Some substances that enter the body are harmless. The body ignores them. An allergy is a specific reaction of your body s immune system to a normally harmless substance. When this happens, the substance that causes the reaction is called an allergen. Other examples of allergens include: Dander from animals. Household dust mites. Mold. In people with hay fever, pollen is an allergen. The body makes a mistake when pollen enters the body. It thinks the pollen could harm the body. The body responds by releasing substances to fight the allergen. One of these substances is histamine. Histamine is made by white blood cells during an allergic reaction. It causes small blood vessels to widen and leak. This can cause tissues to swell. It also causes muscles to contract and the heart rate to increase. It is unclear why some people have allergies and others do not. Allergies may be hereditary. This means that they are passed from parents to their children. Diagnosis Your health care provider will first ask detailed questions about your personal and family medical history. The symptoms of hay fever are similar to the symptoms of other common illnesses. For this reason, your health care provider will also perform a physical exam. This can help reveal whether your symptoms are caused by hay fever or another health problem. If your health care provider thinks that your symptoms are caused by an allergic reaction, he or she may recommend allergy testing. There are two tests that are often used to identify allergies: Skin prick test. Allergy blood test. 3

4 During a skin prick test, a small amount of material that can trigger an allergy is pricked into the skin on the upper arm or back. This is done using a very small needle. Most people learn which allergens cause a reaction after the skin prick test. After placing the allergens into the skin, a health care provider watches the skin for signs of an allergic reaction. If you have an allergy, your skin will become red and itchy at the site of the needle prick. This test takes about an hour. An allergy blood test can measure your body s response to a specific allergen. It measures the amount of special allergy-causing substances in your blood. A blood sample is sent to a lab and tested for sensitivity to possible allergens. It can take several days to find out the results from an allergy blood test. The benefit is that this type of test does not cause a person to have symptoms of an allergic reaction. Treatment The best treatment for any type of allergy is to avoid the substances that cause a reaction. But with hay fever this is very difficult. The pollen that causes the reaction is carried in the air. If hay fever is not severe, over-the-counter medicines may be enough to treat your symptoms. For example, antihistamines can help relieve itching, sneezing and runny noses. This type of medicine is available in the form of a pill or nasal spray. Other over-the-counter medicines that may help treat an allergic reaction include: Cromolyn sodium, which prevents the release of histamine. Decongestants, which help with a stuffy nose and congested throat. Skin Prick Test Prescription medicines are available for symptoms that are mo re difficult to treat. Prescription medicines may come in the form of a pill, nasal spray or eye drop. They work best when you take them exactly as prescribed, which is often once or twice each day. 4

5 Prescription medicines that may help treat an allergic reaction include: Corticosteroids, which help relieve itching and congestion. Leukotriene modifiers, which treat congestion and mild asthma. Nasal ipratropium, which helps treat a severe runny nose. Many people get the best relief by using both prescription and over-the-counter medicines. Decisions about which medicines to take should be made with the help of your health care provider. Other treatments for hay fever include: Allergy shots, also known as immunotherapy. Rinsing your sinuses. Allergy shots may be used when medicines do not relieve your hay fever symptoms. They often are given over a period of three to five years. During that time, you receive shots on a set schedule. Each shot contains a tiny amount of allergen. The goal of treatment with allergy shots is to get your body used to the allergens that cause your symptoms. This helps reduce your need for medicine. Allergy shots are very effective when used to treat pollen allergy. Many people rinse their sinuses to treat hay fever symptoms. It does not cost a lot of money and quickly relieves nasal congestion. It involves pushing or pouring water into one nostril to clear the allergens from your nose and throat. You can rinse your sinuses at home using a squeeze bottle or a neti pot. A neti pot is a small container with a spout designed for nose rinsing. It is important to follow the directions about proper use and cleaning of the bottle or pot to prevent infections. If you have a pollen allergy, talk to your health care provider about these and other treatments. He or she can discuss common side effects for each treatment and help you find the one that best meets your needs. Prevention There is no proven way to prevent getting hay fever in the first place. Health care providers are uncertain why some people get hay fever while others do not. But you can take steps to prevent the symptoms caused by a pollen allergy. 5

6 It is not possible to completely avoid allergens. Even staying indoors with the windows closed when the pollen count is high might not be enough to prevent it. The best thing you can do to prevent hay fever symptoms is learn which specific allergen causes the symptoms and limit your exposure to it. To limit exposure to pollen in your home or car: Close doors and windows, use air conditioning. Use special allergy-free vent filters with air conditioning units. Use a HEPA filter to keep the air clean in your bedroom. Dry your laundry indoors so pollen can t stick to it. HEPA stands for high-efficiency particulate air filter. To limit exposure to pollen outside of the home: Avoid early morning activity outdoors when pollen counts are highest. Avoid yard work such as mowing or raking. Stay indoors on dry, windy days. Use allergy medicine as directed. Wear a dust mask when doing outdoor activities. Using medicine to prevent symptoms often works best when it is taken before exposure to an allergen. Talk to your health care provider about which allergy medicine is right for you. Once you have the medicine, take it as prescribed. Summary Hay fever is a very common allergic reaction to pollen. Hay fever does not mean you are allergic to hay. In fact, hay fever is almost never triggered by hay. It also does not cause a fever. A better term to describe the real cause of hay fever is pollen allergy. Hay fever can also cause the following symptoms: Runny nose. Sneezing. Itching. Swelling. Asthma. Anaphylaxis, which can cause death. 6

7 If your health care provider thinks your symptoms are caused by an allergic reaction, he or she may recommend testing. There are two tests that are often used to identify allergies: Skin prick test, which tests your skin for a reaction. Allergy blood test, which tests your blood for a reaction. Treatment for hay fever is available. Over-the-counter and prescription medicines often provide the most relief when used together. Some people benefit from a series of allergy shots. Allergy shots help the body get used to an allergen so that it does not cause such severe symptoms. There is no proven way to prevent getting hay fever in the first place. Health care providers are uncertain why some people get hay fever while others do not. But by taking steps to limit your exposure to pollen you can better control your symptoms. 7