According to WHO, Asthma is chronic disease characterized by recurrent attacks of breathlessness
and wheezing, which vary in severity and frequency from person to person symptoms may occur several times in a day or week in affected individuals and for some people become worse during physical activity or at night time.
There are two types of asthma: Allergic or Extrinsic and Idiosyncratic or Intrinsic . Allergic asthma is a result of an Antigen / Antibody reaction on mast cells in the respiratory tract. Indiosyncratic asthma is result of neurological imbalances in the autonomic nervous system in which the alpha and beta- adrenrgic as well as cholinergic sites of ANS are not properly coordinated .
During an asthma attack the lining of the bronchial tubes swell, causing the airways to narrow and reducing the flow of air into and out of the lungs.
Recurrent asthma symptoms frequently cause sleepnessless , daytime fatigue, reduced activity levels and school and work absenteism.
Asthma is currently worldwide problem with increasing prevalence in both children and adults. Total prevalence is estimated to be 7.2% of the worlds population [ 6% in adults and 10% in children ]
The total number of people with asthma, however is already higher in the developing world than in industrialized countries. There are approximately 3 million asthamatic in Japan and in France, compared to estimated more than 15 million in India and over 30 million in Africa.
Asthma was not generally considered to be a fatal illness and this was the teaching in medical schools well into the present country . It was not until the rise in deaths from asthma in the 1960s that attitudes began to change.
About 60% of all asthmatics visit their physician at least once a year regarding their condition. Office visits doubled from 1975- 1994 Emergency department visits and hospitalizations are also increasing with 466,000 hospitalizations in 1993 and 1.9 million ED visits in 1995.
