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Hay fever (seasonal allergic rhinitis)Published by Bupa's health information team, healthinfo@bupa.com, August 2007. This factsheet is for people with hay fever, or who would like information about it. Hay fever is also known as seasonal allergic rhinitis. Some of the symptoms include sneezing, a runny nose and itchy eyes. The condition affects about 15 percent of people in the UK and a quarter of people aged between 11 and 21. It seems to be becoming more common worldwide, especially in children.
What is hay fever?If you have hay fever, it means that you are allergic to pollen and/or fungal spores. These are allergens - substances that can cause an allergic reaction. Your allergic reaction happens when your body's immune system mistakes the allergen for a harmful invader. Allergens aren't usually harmful and most people aren't sensitive to them. You may be allergic to other allergens, such as house dust mites, pet hair and moulds. This is perennial allergic rhinitis and means you have it all year round. Hay fever, asthma, food allergy and eczema are related allergic conditions and the tendency to develop them seems to run in families. This is called atopy and means that your body produces an antibody called immunoglobulin E (IgE) when you come into contact with an allergen. If you have hay fever, when there is a lot of pollen in the air you will produce IgE in reaction to it. SymptomsHay fever affects everyone differently and you may have one or more from a range of symptoms, including:
In some people, pollen may also trigger asthma. CausesIf you have hay fever, when you come into contact with pollen or fungal spores, IgE antibodies are produced. Antibodies are usually only released to fight infection, but in this instance your body believes the pollen or spore is harmful. This leads to certain cells in your body, especially those of your respiratory (breathing) system, releasing chemicals. One of these is histamine, which triggers the symptoms of hay fever. You may be allergic to one or more types of pollen - this will determine when your symptoms are most severe. Some possible causes include:
The pollen season can vary depending on where you live. In the UK, the pollen season usually starts earlier in the south and lasts until later in the year in the north. DiagnosisYour GP will usually be able to tell if you have hay fever by asking about your symptoms and when you get them. He or she may look inside your nose and down your throat to make sure you don't have any other conditions that could be causing your symptoms. You probably won't need to have special tests, but very occasionally your GP may advise you to have a skin prick allergy test to help determine if you are allergic to a specific pollen. He or she may also do a blood test to measure the level of IgE antibodies in your blood. Although skin prick tests are usually reliable, some reasons for inaccurate results are listed here.
TreatmentThere are measures you can take to make life as comfortable as possible. However, your GP may also prescribe medicines to ease your symptoms. There is a range of treatments available - you can buy some of these medicines over the counter. You should always get advice from your GP or pharmacist before starting any medication, even if you don't need a prescription for it. Always follow the instructions on the patient information leaflet that comes with the medicine. Some medicines may take a while to have an effect so it's best if you can start taking them before your symptoms start. You may not notice an immediate improvement, but it's usually worth carrying on taking them for a few weeks. Nasal sprays and dropsNasal sprays and drops can help if you have problems with your nose. There are many different types including:
Eye dropsThese can help if you suffer from itchy eyes. There is a wide range on offer, some of which contain antihistamines and others sodium cromoglycate. You may be prescribed nedocromil sodium if your symptoms are more severe. TabletsIf you don't like using eye or nose drops, you may find tablets helpful. These usually contain antihistamines, which work to reduce sneezing, watering eyes and an itchy mouth and throat. It's important that you are aware that some antihistamines can make you feel drowsy. Ask your GP or pharmacist for advice and always read the patient information leaflet that comes with your medicine. ImmunotherapyIf all other treatments have failed to relieve your hay fever symptoms, you may be advised by a specialist to try immunotherapy. This will involve being given doses of the pollen to which you are allergic over a period of time. One such treatment is phleum pratense (Grazax). This is a new grass pollen vaccine that you take by placing a tablet under your tongue. It has just been released for prescription in the UK. It needs to be taken on a daily basis for at least eight weeks, although probably longer than this, before the start of the summer pollen season. It may be suitable if you are over 18 and your grass pollen hay fever is not controlled by over-the-counter medicines. Although the first dose needs to be given by your GP or specialist, after that you can take the tablets at home. The drug doesn't seem to have any serious or long-lasting side-effects, although you may have an itchy mouth for a short while. Studies are being carried out to see if the medicine is more effective if you take it for several years. There have been some cases of immunotherapy causing serious side-effects. However, recent studies have shown that these are rare and the benefits outweigh the risks. The pollen countThis is the average number of pollen grains in one cubic metre of air over 24 hours. Pollen counts are done daily for grass, tree and weed pollen. Pollen forecasts predict how high the pollen count will be. This can be useful in helping you decide when will be the best time to start treatment. The weather can affect the pollen count with it being higher on sunny days and lower on rainy days. SteroidsIf you have severe hay fever, you may need stronger medication to deal with the symptoms. This may also be an option if you need fast relief (for example, if you have to sit an exam). In these cases, your GP may prescribe you a short course of steroid tablets - your dose can be adjusted according to the pollen count and you can stop taking the tablets straight away if you have any side-effects. You can use other treatments such as nasal sprays while taking steroids. PreventionThere are a number of things you can do to help reduce your symptoms. Some of these include:
Further information
Sources
www.allergyuk.org/art_hayfever.aspx accessed 18 April 2007 Related topicsThis information was published by Bupa's health information team and is based on reputable sources of medical evidence. It has been peer reviewed by Dr Andrew Barlow MSc MRCP MBChB(Hons) BSc(Hons), consultant physician at Watford General Hospital and the Royal Brompton Hospital, and Dr James Quekett Bsc MBChB MRCGP DRCOG DFFP, partner/principal general practitioner at Rowcroft Medical Centre, and by Bupa doctors. The content is intended for general information only and does not replace the need for personal advice from a qualified health professional. Publication date: August 2007. Expected review date: August 2009.
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