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WHAT IS HAYFEVER?

 

Hayfever, also known as allergic rhinitis, is an allergic reaction to particles that enter the nose and throat.

 

• Hayfever is the most common of all allergies, affecting 10-15 per cent of the population. Its incidence is rising, though the reasons for this are unclear. 
• Hayfever is more common in boys than girls. Children from well-off families and single and first-born children are more susceptible. Many doctors believe that this may be because such children are not exposed to enough infections and foreign substances during the first few years of life. 
• There are two types of hayfever: the first is seasonal (mainly spring and summer) allergic rhinitis; the second is perennial (all year round) allergic rhinitis. 

What triggers hayfever

 

Hayfever is an allergy that can be triggered by many different proteins entering the body. The triggers can vary from person to person.

 

• Hayfever occurs when the body reacts with unusual sensitivity to a substance (known as an allergen). When the substance is next present, the body's antibodies mark it and attract defensive cells, some of which are called mast cells. These release chemicals such as histamine. 
• Histamine is a substance that causes an inflammatory response and produces allergy symptoms. 
• Hayfever allergens include tree pollens in the spring, grass pollen in the summer and mugwort and hybrid flowers, such as chrysanthemums, in the autumn. Other allergens include dried cat saliva and skin from pets. Perennial hayfever can be caused by the droppings of house dust mites and the spores from fungal moulds. 
• Nasal hypersensitivity to tobacco smoke and dust, for example, can exacerbate symptoms. 

What happen during an attack?

 

The symptoms of hayfever vary according to how the body reacts to specific allergens and the amount of histamine that is produced.

 

Allergic reaction: histamine contracts smooth muscles, such as those of the airways, and widens small arteries and blood vessels, which become more permeable, allowing fluid to escape into the tissues. This causes the membranes to become swollen and inflamed.

 

Symptoms: the result of an attack can be frequent sneezing, with either a runny or congested nose, coughing, watery, itchy, puffy eyes and sometimes wheezing and a burning sensation in the throat.

 

Duration: symptoms may subside, only to reappear two to 12 hours later when more histamine is released from slower-reacting mast cells.

 

NOTE: sufferers from perennial allergic rhinitis may have low-grade symptoms throughout the year, often worse in the morning and evening, with occasional severe attacks.

 

The symptoms of hayfever can be very irritating for the sufferer. The eyes often become itchy and appear puffy during an attack.

 

Medical treatments

 

Even though there is no known cure for hayfever, the symptoms can be treated successfully

 

• Antihistamines are used in the first instance to alleviate symptoms such as sneezing, a runny nose and watery eyes. Decongestants may also provide some relief. 
• Corticosteroid sprays, administered to the membranes of the nose, are often effective in reducing inflammation. 
• For cases where steroids are ineffective, a drug called sodium chromoglycate (cromolyn) may be used in the form of eye drops or a nasal spray. 
• A medication called ipratropium bromide may be given to combat a runny, itchy nose. 
• Desensitisation therapy, or immunotherapy, involves 'challenging' the sufferer by exposure to repeated and increasing doses of the allergen in an attempt to desensitise the body

However, great care must be taken because of the risk of a drastic reaction to the allergen (anaphylactic shock).

 

Self-help measures

 

The basis of all self-help measures is to avoid exposure to the allergen once it has been identified.

 

Avoidance: if the allergen that causes your child's hayfever is a pollen, find out in which months it appears and take precautions to avoid contact. Find out at what time of day the pollen allergen is released. For example, ragwort pollen is released from dawn to around 9 a.m., while grass pollen is released from 7.30-10 a.m. Some hayfever sufferers find it useful to wear sunglasses and a mask when they are outside during vulnerable times

 

Cleanliness: house dust mites and mould flourish in warm, humid, still conditions. Buy a dehumidifier to discourage them, and wash all loose fittings frequently at a high temperature. Wet wash furniture to remove dust and try to vacuum all carpets, bedding and cushions at least twice a week.

 

The outlook

 

There is no permanent cure: for hayfever, but some sufferers. find that the symptoms diminish as they get older

 

• Most hayfever sufferers are first sensitised to an allergen in early life, .but the condition does not become apparent until childhood or the teenage years. Less commonly, hayfever develops later in life. 
• Generally, hayfever sufferers find that their symptoms become much less severe by the time they are in their 30s and 40  hayfever. 

LINKS WITH OTHER ALLERGIES

 

Even though there is no known cure for hayfever, the symptoms can be treated successfully.

 

• Some people have an inherited tendency to develop allergies, and are said to be atopic. In such people, particularly, allergies may change and new ones develop over time. For example, between 40 and 60 per cent of children who suffer from eczema go on to develop hayfever or asthma in later life. 
• Some hay fever sufferers develop a form of asthma known as pollen asthma. Some doctors believe that this is triggered by inhaled pollen; others that an attack of hayfever makes the airways hypersensitive to asthma triggers, such as cold air and exhaust fumes. 

For  More  Information:  Please  consult  your  physician  on  your  next  visit.