If you have ever witnessed someone having an asthma attack you will know how frightening it can be. For a lot of sufferers the fear of having an asthma attack can be as much of a worry as the attack itself.

There are several types of asthma, many of which are not related to allergies but arise from non-immune hypersensitivity of the airways to irritants such as cigarette smoke or other factors such as exercise and the weather.

Allergic asthma, as the name suggests, is when an allergy manifests itself as an asthma attack. This is usually due to an airborne allergen, for example pollen or animal dander, entering the lungs and launching an allergic reaction in the local area, but it is also quite common for food allergies, especially to dairy products, to trigger an attack.

It is an atopic disease, which means it is most common in people who are genetically predisposed to overproduction of IgE, which is why allergic asthma often runs in families. Another atopic disease, eczema, occurs simultaneously in roughly 50% of sufferers.

The symptoms of asthma can be managed well nowadays with drugs, but the best defence is to work out what triggers your asthma and find ways to avoid it.

Asthma in later life

Although some people outgrow their asthma, it will remain with most sufferers for life. It is even possible for new cases to develop in the senior years, which can be a little unnerving especially when it is complicated by other conditions that come with advancing age.

Things can become particularly problematic when an asthmatic requires drug treatment for another condition. ACE inhibitor drugs used to treat high blood pressure or beta-blockers taken for glaucoma are known in many to provoke asthma attacks, while non-steroidal anti-inflammatory drugs such as aspirin, ibuprofen and naproxen can all induce what is known as aspirin-induced asthma, where an attack is provoked on ingestion.

Aspirin-induced asthma affects between 10 and 20% of asthmatics and is a common complication of adult-onset asthma, the average age for its first appearance being 46. The exact mechanisms of the condition are not yet fully understood, but it is thought that the cause is an overreaction of the immune system similar to other types of allergic asthma.

In addition to drug complications, the symptoms of other conditions such as heartburn and respiratory infections can sometimes be enough to bring on an attack, and the stress and worry of any type of illness may contribute to the condition, a situation not helped when increasing age begins to take its toll on the other systems of the body.

The symptoms of allergic asthma occur when inflammation of the lower airways is caused by histamine release from an allergic reaction. The airways become narrowed and so the flow of air in and out of the lungs is obstructed, resulting in the classic symptoms of an asthma attack:

• Tightness of the chest
• Difficulty breathing
• shortness of breath  in severe cases causing inability to move or talk
• Wheezing
• Coughing
• Tiredness
• Inability to tolerate exercise

Asthma attacks can vary in severity from a minor coughing fit to a life-threatening inability to breathe, depending on how sensitised the individual is and how quickly they receive treatment. Most asthmatics are able to pre-empt a full-blown attack by using preventative treatment, or by recognising the initial symptoms and using an inhaler loaded with a reliever.

Treatment

Most sufferers tend to manage their condition in four ways:
1. Avoiding their allergens
2. Using medication to prevent the inflammation
3. Using medication to relieve the symptoms of inflammation.
4. Steroid treatment  a last resort for severe cases due to side effects.

Allergen avoidance

If your asthma is triggered by airborne allergens around the home such as dust mite excrement and animal dander you can significantly reduce their numbers by frequent washing of clothes, bedding and soft furnishings in very hot water.

Anti-allergy cleaning fluids and allergen-tight bedding are also extremely effective at preventing attacks and by swapping carpets for floorboards and maintaining good ventilation you can significantly reduce the number of allergens in your home.

If your asthma is triggered by a food allergy, you should avoid that food by reading labels and asking questions when eating out.

Preventative drugs

These are drugs that asthmatics use on a regular basis to help keep symptoms at bay. They can be taken both in tablet form and through an inhaler. They are anti-inflammatory drugs such as chromoglycate, which helps to control the inflammation of the airways that causes the symptoms. Asthmatics will often use these when they first notice symptoms or when they are likely to be triggered, in order to prevent an attack.

Reliever drugs

Reliever drugs known as bronchodilators are used to help relieve the symptoms of asthma as they occur. They act immediately to reduce the narrowing of the airways and are generally used only as a short-term remedy. Longer-lasting drugs called theophyllines can be used if the bronchodilator drugs are ineffective.

Steroid treatment

Steroids act by suppressing inflammation and are a very effective way to treat asthma. Due to the nature of their side effects if used over a prolonged period, which include nausea, vomiting, weight gain and raised blood pressure, such treatments are usually only employed as a last resort.

Anti-leukotrienes

A new group of drug called anti-leukotrienes have recently started being used to treat asthma. These drugs, such as montelukast, zafirlukast and zileuton are given in tablet form and act as an anti-inflammatory and a bronchodilator, so they are useful both in treating the symptoms and managing the cause.

Using anti-leukotrienes regularly can mean a significant reduction in the necessary dosage of other treatments.

19/05/2009