Hay Fever

Hay fever

The balmy days of summer herald the beginning of the hay fever season for many sufferers. Although this miserable condition is not curable, modern treatments are much more effective at keeping symptoms under control.

Hay fever is one of the most common types of allergic disease, affecting at least one in 10 people. During the last few decades, the number of reported sufferers has increased substantially, possibly as a result of increased pollution from car fumes. Luckily, more effective treatments have developed at the same time.

The term hay fever, or allergic rhinitis as doctors call the nasal symptoms, refers to inflammation of the lining of the nose, caused by an allergic response to certain otherwise harmless substances found in the air. The medical term for these is 'allergens'.

A physician named Charles Blackley, himself a hay fever sufferer, first recognized the disease in 1873. He proved that breathing in pollen grains could provoke sneezing, a runny or blocked nose and sore, red eyes.

In an attack of hay fever, the allergens trigger an exaggerated response from the immune system. Chemicals, including histamine, are released into the system. These cause the delicate lining of the nose to swell and watery fluid to leak from it. The membrane covering the whites of the eyes and the inside of the eyelids is also affected.

Typical symptoms can include a running or blocked nose; sneezing; itchy nose, palate and ears; sore, watery, puffed eyes; a raw-feeling throat and sometimes wheezing and a dislike of bright light.

WHO GETS HAY FEVER ?

Hay fever is known as an atopic condition, which means an allergic condition tending to run in families, like asthma or eczema.

The worst sufferers are children aged five to 14, particularly boys, but women suffer more than men in the 15 to 44 age group. After the mid-40s, the seasonal type of allergic rhinitis tends to become gradually less troublesome.

The term hay fever is often used to refer to any type of allergic rhinitis, whether it is confined to those times of the year when pollen is the most common culprit or whether it is present more or less all year round. In the latter case, the most likely allergens are the droppings of the house dust mite, the spores released by certain moulds, or furry or feathered pets.

AIR POLLUTION

Evidence is now mounting that air pollution may either trigger hay fever attacks in pollen-sensitive sufferers or make existing attacks worse. High levels of the pollutants ozone and nitrous oxides have been particularly implicated.

A diet high in vitamin C, which is found in citrus fruits, bell peppers, strawberries and blackcurrants, and vitamin E, found in nuts and seeds, often helps damp down the inflammatory response.

The doctor normally diagnoses hay fever by taking a careful history of the patient's symptoms, paying particular attention to how and when they occur.

The diagnosis can be confirmed by the 'skin prick test', although this isn't always necessary. Different allergens, such as extracts of grass, tree and weed pollens as well as fungal spores, are injected just under the skin. Hay fever sufferers should exhibit a 'weal and flare' response within five to 15 minutes. The skin reddens and a fluid-filled blister develops at the site of the needle puncture.

Hay fever is rare before the age of five. However, it is possible that babies who are constantly snuffly and have trouble feeding may be showing signs of hay fever. In small children, hay fever often causes them to rub their noses upwards and breathe through their mouth. Dark circles may develop under their eyes.

Some chronic hay fever sufferers may develop nasal polyps -- moist bluish-white swellings, often on stalks, that can obstruct their nose and interfere with their sense of smell. Nasal polyps can be removed surgically but sometimes they can recur.

WHAT ARE THE TREATMENTS ?

The first step is to try and reduce exposure to the allergens to which you are sensitive. If the house dust mite is the culprit, damp dusting daily, sealing mattresses within spongeable covers, replacing carpets with hard floors and using a more efficient vacuum cleaner can help enormously.

Mild hay fever sufferers often manage to cope without drug treatment. Others only use it for important occasions, for instance sitting examinations. It helps to think ahead and consult your doctor about treatment a couple of weeks before you expect your symptoms to start.

Antihistamine tablets are a traditional remedy for hay fever. As the name suggests, the tablets block the action of histamines that cause inflammation. Unfortunately, they only seem to work for about half of those who try them and they can often cause drowsiness. However, a new generation of antihistamines is now available, such as terfenadine and loratadine, which have virtually eliminated this problem. Like many other treatments, all antihistamines are much more effective when they are taken before an attack begins rather than during one.
NEW TREATMENTS
Aerosol steroids which also damp down the immune response are safe and very effective when used carefully and in small amounts. The symptoms they are particularly effective at treating are blocked or runny noses and sneezing. In very severe cases, steroids need to be given by mouth or injection.


Nose drops based on herbs like ephedrine shrink the surface blood vessels, thereby reducing swelling in the nose and relieving the characteristic watery discharge from the nose. They are popular because they have an immediate action. However, the drops lose their effectiveness if they are used too frequently and can cause the lining of the nose to swell even more in between doses. For this reason, they should never be used for more than a few days at a time.


Sodium cromoglycate prevents symptoms from developing rather than treating them. It should therefore be used when no symptoms are present or when they are already under control.
TOLERANCE LEVELS
De-sensitizing treatment, known as hypo-sensitization treatment or immunotherapy and which reduces the sufferer's sensitivity, is more controversial. The theory behind it is that it is possible to develop a tolerance to allergens.


This is performed by injecting the sufferer with small quantities of the substance to which he is allergic. With each injection, the quantity of allergen is gradually increased. If the treatment is successful, the allergic reaction is eventually diminished.


However, this treatment is now usually reserved for those hay fever sufferers who fail to respond to any other type of treatment, as it generally only provides partial relief from their symptoms.


More worrying, though, is that allergens can be dangerous and, on rare occasions, immunotherapy has been known to provoke anaphylactic shock -- a severe, life-threatening allergic response. For this reason, it's most important that the patient remains within close reach of emergency medical facilities for at least an hour after each injection of an allergen.
FUTURE TREATMENTS
Looking into the future, it seems quite possible that a type of gene therapy could be specially devised for hay fever. This would switch off the atopic gene which makes some people over-react to harmless substances and triggers hay fever and asthma. This would effectively provide a cure for these conditions.

Continue reading here: Noise pollution

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