ASTHMA THERAPHY

Worldwide, it is estimated that 330 million people suffer from asthma. In the UK, there is a person with asthma in one in five households. One in ten UK children suffer from the condition - this corresponds to over 1.1 million young people. Asthma is not just a public health problem for 'developed' countries - over 80% of asthma deaths occurs in low and lower-middle income countries It is predicted that without urgent action asthma deaths will increase by almost 20% in the next 10 years.

Description of asthma
Asthma is a chronic disease that affects your respirations on the airways. The airways are the tubes that carry air in and out of your lungs. If you have asthma, the inside walls of your airways are inflamed (swollen). The inflammation makes the airways very sensitive, and they tend to react strongly to things that you are allergic to or find irritating. When the airways react, they get narrower, and less air flows through to your lung tissue. This causes symptoms like wheezing (a whistling sound when you breathe), coughing, chest tightness, and trouble breathing, especially at night and in the early morning.

The other description : Asthma is an allergic reaction, provoked by any one of 200 irritants, or allergens, such as the house dust mite, cat dander, pollen, or certain foods. Attacks can also be brought on by exercise, emotional disturbance and infections like bronchitis. The underlying causes are not known, although there appears to be a genetic component. Prevention, by avoiding exposure to allergens, would be the ideal solution, but this is far from easy and in many cases is impossible. Asthma cannot be cured, but most people with asthma can control it so that they have few and infrequent symptoms and can live active lives.

While there is no evidence that air pollution causes asthma, it can aggravate the condition in people who are already susceptible. Hence during periods of poor air quality, there is a rise in the number of hospital admissions due to acute asthma attacks.
Asthma is a narrowing of the airways of the lungs, made worse by allergens and eased by medication. The inflamed airways become irritable, leading to bouts of coughing, wheezing, breathlessness and chest tightness. The symptoms can be reversed by treatment, but they can be severe and are sometimes fatal.
When your asthma symptoms become worse than usual, it is called an asthma episode or attack. During an asthma attack, muscles around the airways tighten up, making the airways narrower so less air flows through. Inflammation increases, and the airways become more swollen and even narrower. Cells in the airways may also make more mucus than usual. This extra mucus also narrows the airways. These changes make it harder to breathe.

'Preventers' or 'relievers' - inhaled medicines used to relieve the symptoms of asthma attacks
Asthma therapy relies on inhaled medicines both to suppress the underlying inflammation and to relieve airway constriction. The former, used regularly as 'preventers', are glucocorticosteroids such as beclomethasone and budesonide. These drugs are based on cortisol, a naturally occurring chemical in the body. Animal studies have played a vital role in the discovery and characterisation of the glucocorticosteroids introduced from the 1960s onwards, most of which are given by inhalation to avoid the effects associated with oral steroids such as cortisol. Sodium chromoglycate is another type of inhaled 'preventer', and interestingly this was discovered in the late 1970s by the scientist and asthmatic, Roger Altounyan, who conducted many experiments on himself.

The second type of inhaled medicines are the bronchodilators or 'relievers' that bring rapid relief from symptoms. Development of bronchodilators in the late 1960s was one result of the discovery of the existence and action of chemical nerve transmitters by Otto Loewi, working on frogs in the 1930s. He discovered that chemicals such as adrenaline are released by nerves and act on receptors in organs such as the heart and lungs. However, later animal experiments revealed that the first bronchodilators were too short acting and stimulated the heart. Further animal work led to more specific bronchodilators which were safer and longer-lasting such as salbutamol and terbutaline. These drugs activate ß2 adrenoceptors located in airway smooth muscle causing muscle relaxation and thus opening of the airways.

Both types of medication in use today, preventers and relievers, are refined and more selective versions of the naturally occurring chemicals. Research on laboratory animals has been important in most stages of the development of these medicines, to identify active molecules, evaluate their safety and find the most effective route of administration.
When your asthma symptoms become worse than usual, it is called an asthma episode or attack. During an asthma attack, muscles around the airways tighten up, making the airways narrower so less air flows through. Inflammation increases, and the airways become more swollen and even narrower. Cells in the airways may also make more mucus than usual. This extra mucus also narrows the airways. These changes make it harder to breathe.

What can we do?
Asthma attacks are not all the same—some are worse than others. In a severe asthma attack, the airways can close so much that not enough oxygen gets to vital organs. This condition is a medical emergency. People can die from severe asthma attacks.
So, if you have asthma, you should see your doctor regularly. You will need to learn what things cause your asthma symptoms and how to avoid them. Your doctor will also prescribe medicines to keep your asthma under control.

Taking care of your asthma is an important part of your life. Controlling it means working closely with your doctor to learn what to do, staying away from things that bother your airways, taking medicines as directed by your doctor, and monitoring your asthma so that you can respond quickly to signs of an attack. By controlling your asthma every day, you can prevent serious symptoms and take part in all activities.

If your asthma is not well controlled, you are likely to have symptoms that can make you miss school or work and keep you from doing things you enjoy. Asthma is one of the leading causes of children missing school.