Sneezing and a runny nose; itchy, red eyes; a cough and fatigue are just of the symptoms most of us will be only too familiar with.
Millions of work days a year are lost due to the condition and it can also affect exam performance in teenagers and quality of life generally.
Hay fever is caused by the body making allergic antibodies, immunoglobulin E (IgE) in response to breathing in pollen from grass, weeds and trees. This causes the release of a chemical called histamine in the nose, eyes or airways, which causes inflammation and irritation.
The pollen season is roughly divided into three time slots: tree pollen is released from late March to mid-May; grass pollen from mid-May to July and weed pollen from the end of June to September. The season can start as early as January and end as late as November, though, and types of pollen change annually. Grass pollen is the most common one and tends to peak around June.
You can check the pollen count daily during pollen season with the free Met Office pollen forecast. Weather and temperature can also increase symptoms: the warmer, drier and stiller the air, the more levels of pollen are suspended in it. Hay fever is twice as common in cities and urban areas and is believed to be linked to increased air pollution. Alcohol can also make hay fever worse, as wine, beer and spirits contain histamine.
Typically, symptoms include recurrent sneezing and a streaming (then blocked) nose, with itchy red, puffy, watery eyes. These symptoms are often accompanied by an itchy throat and headache. You may also feel tired as hay fever can interfere with sleep. If you have asthma, symptoms such as breathlessness and wheezing can worsen during the pollen season.
Most people diagnose themselves and either buy over the counter remedies or get a GP prescription.
Occasionally, a skin prick or blood test will help to check which pollens are triggering your hay fever, a hospital consultant allergy specialist can do this test.
Who gets hay fever?
If your parents suffer with allergies or you are atopic (have eczema or asthma) you are at higher risk of hay fever. Asthma UK say 80 per cent of those with asthma also have a pollen allergy. Equally, if you have hay fever you are more likely to go on and develop eczema and asthma.
Children aged five to 14 and 15 to 24 year-olds tend to be those most affected. Symptoms can improve as you get older, with around 10 to 20 per cent of people reporting they disappear completely, however, some people get hay fever for the first time in their 40s.
For most people, treatment is a combination of avoiding pollen and using over the counter medication. To avoid pollen, keep your windows closed when indoors and don’t put your washing outside to dry. When you are outdoors, protect your eyes with wraparound sunglasses and apply a balm like petroleum jelly inside your nostrils as a pollen barrier. You should also change your outdoor clothes when you get in, and ideally, have a shower and wash your hair to get rid of any pollen spores.
Antihistamines, over the counter medications to help block the production of histamine, can reduce inflammation of the nose and throat. Saline (salt) douching can clear the nose of allergens, while topical nasal corticosteroid spray or drops can help reduce inflammation and swelling in the nose. Sodium cromoglicate drops can soothe irritated eyes.
It's recommended you start using nasal corticosteroid sprays and sodium cromoglicate eye drops two or three weeks before the pollen season begins to help prevent symptoms.
Immunology or desensitisation is a line of treatment for severe sufferers that involves gradually exposing allergy sufferers to tiny, but increasing amounts, of pollen either by injection or pill to help build up immunity to allergens. This is done under the supervision of a consultant allergy specialist. A new study has shown this treatment needs to be carried out over a period of at least three years though to become fully effective. Once it is, though, it could mean sufferers are symptom-free and no longer have to rely on nasal sprays and antihistamines.