Hay fever is a common allergic condition that affects up to one in five people at some point in their life.
Symptoms of hay fever include:
- a runny nose
- itchy eyes
The symptoms of hay fever are caused when a person has an allergic reaction to pollen.
Who is affected?
Hay fever is one of the most common allergic conditions. It is estimated that there are more than 10 million people with hay fever in England.
Hay fever usually begins in childhood or during the teenage years, but you can get it at any age.
The condition is more common in boys than in girls. In adults, men and women are equally affected.
Being exposed to tobacco smoke during early childhood is a risk factor
Hay fever symptoms vary in severity and may be worse some years than others, depending on the weather conditions and the pollen count. The time of year your symptoms start depends on the types of pollen you're allergic to.
The symptoms of hay fever include:
Hay fever and asthma
If you have asthma, your asthma symptoms may get worse when you have hay fever. Sometimes, asthma symptoms only occur when you have hay fever.
These symptoms include:
- tight chest
- shortness of breath
Many people find that their symptoms improve as they get older. Around half of people report some improvement in symptoms after several years. In around 10%-20% of people symptoms go away completely.
Causes of hay fever
Hay fever is an allergic reaction to pollen. This affects your body in the following way:
- When these tiny particles come into contact with the cells that line your mouth, nose, eyes and throat, they irritate them and trigger an allergic reaction, to become swollen, irritated and inflamed.
- When you have an allergic reaction, your body overreacts to something it perceives as a threat. In hay fever, the allergen (the substance you are allergic to) is pollen. Your immune system (the body’s natural defence system) starts to respond as if it were being attacked by a virus.
- Your immune system will release a number of chemicals designed to prevent the spread of what it wrongly perceives as an infection.
- These chemicals then cause the symptoms of the allergic reaction, such as watering eyes and a runny nose.
What is pollen?
There are about 30 different types of pollen, with different trees and plants producing their pollen at different times of the year, so depending on which pollen you are allergic to, you may experience your hay fever symptoms at different times. It's possible to be allergic to more than one type of pollen. Research suggests that pollution, such as cigarette smoke or car exhaust fumes, can make allergies worse.
when is pollen at its worst?
That depends on what kind of pollen you are allergic to. In the UK, the pollen count season is usually separated into three periods:
- tree pollen, released during spring - about 25% of people in Britain with hay fever are allergic to pollen from trees, including oak, ash, cedar and birch (people with an allergy to birch often also experience an allergic reaction to apples, peaches, plums and cherries as these types of fruit contain a similar protein to birch pollen)
- grass pollen, released during the end of spring and beginning of summer - 90% of people in Britain with hay fever are allergic to grass pollen
- weed pollen, released any time from early spring to late autumn - such as dock, mugwort and nettles
However, the pollen count season can sometimes begin as early as January, or end in November.
What is the pollen count?
Hay fever symptoms are likely to be worse if the pollen count is high. The pollen count is the number of grains of pollen in one cubic metre of air.
more information about the pollen count
Air samples are collected in traps set on buildings two or three storeys high. Taking samples from this height gives a better indication of the pollen in the air.
Traps on the ground would only collect pollen from nearby trees and plants.
The air is sucked into the trap and the grains of pollen are collected on either sticky tape or microscope slides (glass plates). The pollen is then counted. Samples are normally taken every two hours, and usually the results are averaged over a 24-hour period.
The pollen forecast is usually given as:
- low: fewer than 30 grains of pollen in every cubic metre of air
- moderate: 30-49 grains of pollen in every cubic metre of air
- high: 50-149 grains of pollen in every cubic metre of air
- very high: 150 or more grains of pollen in every cubic metre of air
Hay fever symptoms usually begin when the pollen count is over 50. The pollen count is usually given as part of the weather forecast during the spring and summer months.
The effect of the weather
The amount of sunshine, rain or wind affects how much pollen plants release and how much the pollen is spread around. On humid and windy days, pollen spreads easily. On rainy days, pollen may be cleared from the air, causing pollen levels to fall.
During their pollen season, plants release pollen early in the morning. As the day gets warmer and more flowers open, pollen levels rise. On sunny days, the pollen count is highest in the early evening.
There is currently no cure for hay fever but most people are able to relieve symptoms with treatment, at least to a certain extent.
In an ideal world, the most effective way to control hay fever would be to avoid exposure to pollen. However, it's very difficult to avoid pollen, particularly during the summer months when you want to spend more time outdoors.
medication for hayfever
Treatment options for hay fever include antihistamines, which can help prevent an allergic reaction from happening and corticosteroids(steroids), which help reduce levels of inflammation and swelling.
Many cases of hay fever can be controlled using over-the-counter medication available from your pharmacist. But if your symptoms are more troublesome it’s worth speaking to your GP as you may require prescription medication.
For persistent and severe hay fever there is also a type of treatment called immunotherapy where you are exposed to small amounts of pollen over time to build up a resistance to its allergic effects. However, this can take many months or even years to be effective.
Self-help tips for preventing hay fever
It is sometimes possible to prevent the symptoms of hay fever by taking some basic precautions, such as:
- wearing wraparound sunglasses to stop pollen getting in your eyes when you are outdoors
- change your clothes and take a shower after being outdoors to remove the pollen on your body
- try to stay indoors when the pollen count is high (over 50). See hay fever symptoms for an explanation of the pollen count
It is very difficult to completely avoid pollen. However, reducing your exposure to the substances that trigger your hay fever should ease your symptoms.
If possible, try to stay indoors when the pollen count is high (over 50). The following tips may help reduce your exposure to pollen:
- Keep windows and doors shut in the house. If it gets too warm, draw the curtains to keep out the sun and keep the temperature down.
- Don't keep fresh flowers in the house.
- Vacuum regularly, ideally using a machine with a HEPA (high-efficiency particle arresting) filter.
- Damp dust regularly. Dusting with a wet cloth, rather than a dry one, will collect the dust and stop any pollen from being spread around.
- Keep pets out of the house during the hay fever season. If your pet does come indoors, wash them regularly to remove any pollen from their fur.
- Don't smoke or let other people smoke in your house. Smoking and breathing in other people's smoke will irritate the lining of your nose, eyes, throat and airways, and can make your symptoms worse.
- If possible, avoid drying clothes outside. This will help prevent bringing pollen into your house.
Avoiding pollen outside
If you need to go outside or are travelling, the following tips may help reduce your exposure to pollen:
- Avoid cutting grass, playing or walking in grassy areas and camping – particularly in the early morning, evening and at night when pollen counts are highest.
- Wear wraparound sunglasses to stop pollen getting in your eyes.
- Change your clothes and take a shower after being outdoors to remove the pollen on your body.
- Keep car windows closed. You can buy a pollen filter for the air vents in your car. This will need to be changed every time the car is serviced.
Hay fever does not pose a serious threat to health but it can have a negative impact on your quality of life. People with very bad hay fever often find that it can disrupt their productivity at school or work.
When to seek medical advice
Most cases of hay fever can be treated using over-the-counter medication.
A pharmacist can advise on treatments for you or your children.
You would normally only need to see your GP if:
- you can't control your symptoms with over-the-counter medications or you are having troublesome side effects caused by the medication
- you are experiencing persistent complications of hay fever, such as worsening of asthma or repeated episodes of sinusitis
- the pattern of your symptoms is unusual; such as occurring during the winter or only at your workplace – it is likely that another substance other than pollen is responsible and further testing will be required to confirm this