Pollen from grass can trigger hayfever, a type of allergy – your doctor may call it seasonal allergic rhinitis. Hayfever occurs when your body makes the mistake of treating the grass pollen as a harmful organism, and the immune system goes into action by making antibodies to try to prevent it spreading. Symptoms of hayfever include sneezing, itchy, even watery, eyes and a stuffy nose. Allergy to grass pollen is the most common type of pollen allergy in the UK, with over 90% of people with hayfever having an allergy to grass pollen.
When does grass pollen trigger allergy symptoms? Grass pollen allergy is seasonal, with pollen on average being released between early May and mid-September. The peak of grass pollen allergy season is between late-May and late July.
Pollen counts – the amount of pollen in the air – can vary. Symptoms normally appear when the count is above 50. Weather and biological factors can have an effect, so the pollen counts – and your symptoms – can be worse in some years than others. Pollen counts are often higher on warmer dry days than cooler wet days as rain removes pollen from the air, and they won’t be the same in every region, so where you live in the country can determine your allergy symptoms.
Can grass pollen allergy be made worse by what I eat? Some people with a grass pollen allergy may have a cross-reaction when they eat certain foods at the same time that grass pollen is in season. This is known as oral allergy syndrome or pollen food syndrome, and occurs when they eat certain fruits, vegetables or pulses, especially in raw form. It occurs because the proteins in the pollen are very similar to those in the foods.
In people with grass pollen allergy, the most common foods that can cause a cross-reaction are:
Melon, Orange, Tomato, Pea, Peanut.
Because the process of digesting the food inactivates the allergen, the symptoms are normally limited to the mouth and throat, involving mild itching and/or swelling of the lips, tongue, mouth or throat. They normally begin within minutes of eating the food, but then calm down within 30 minutes to an hour. Cooking the food can inactivate the allergen, which is why cooked foods are less likely to trigger symptoms. Additionally, beer, wine and spirits contain histamine – the chemical responsible for allergy symptoms – so alcohol can make hayfever symptoms worse.
What can I do to control a grass pollen allergy? You can try to limit your exposure to grass pollen to reduce symptoms, but avoiding it altogether would be difficult as windborne pollen can travel for miles. During grass pollen season you can try the following suggestions:
Follow pollen forecasts every day (the Met Office provides a website that indicates when pollen counts are high) – if they are high, between 50 and 150 – try to stay indoors.
Avoid going outside on windy days or after a thunderstorm, when pollen is blown about.
Avoid outdoor trips to inland rural areas – sea breezes will blow pollen inland, so consider coastal trips instead.
Prevent pollen from entering your nose by applying an effective barrier inside your nostrils – you can use an appropriate balm or gel nasal spray or even petroleum jelly.
Keep pollen out of your eyes by wearing wrap-around sunglasses. Avoid mowing lawns and raking leaves, or wear a filtration face mask while doing these activities. Ensure the lawn is mowed often so it is less likely to produce flowers and do not leave grass cuttings on the lawn.
Consider replacing lawn with gravel or paving. If travelling by car along dual carriageways or motorways with grass verges, keep the car windows closed and keep the air on ‘re-circulate’ to avoid bringing pollen in outdoor air inside the car; if you are purchasing a car, look for one with a pollen air filter.
After being outdoors, you may want to change your clothing (before going into your living room or bedroom) and wash your hair to remove any pollen. Bring in washing before the evening when pollen counts increase, and don’t hang washing outside when pollen counts are high.
When indoors, keep your windows closed, particularly in the early morning, when pollen is being released, and in the evening, when pollen carried in the air begins to fall closer to ground level as the air cools down. People who struggle considerably with grass pollen may want to consider air-conditioning.
Avoid irritants such as tobacco smoke and insect sprays, which can make symptoms worse.
Treatments for the symptoms of grass pollen allergy are the same for all allergic rhinitis, which includes the use of antihistamines and steroid nasal sprays. Your GP or pharmacist can recommend which treatment is best for you. If you use nasal sprays to control the symptoms of grass pollen allergy, the National Institute for Health and Care Excellence (NICE) advises to restart treatment at least 7 days before the start of the grass pollen season, and if that is uncertain, then start treatment a few weeks before the season is likely to start.