Asthma is obstructive lung disease that affects the bronchial airways. Also called Reversible obstructive air way disease (ROAD). In asthma the bronchial tubes are plugged with excessive mucus, even there is bronchial wall inflammation. Inflammation causes the muscles to contract and go to under spasm resulting in wheezing.

 

New classification in types of asthma

Until recently, bronchial asthma was divided into two defined types of asthma

• Extrinsic (allergic) asthma
• Intrinsic asthma (non-allergic) asthma

Today asthma is divided into number of different types

• Allergic (Extrinsic)
• Non Allergic (Intrinsic)
• Mixed asthma
• Exercise induced asthma
• Nocturnal asthma
• Occupational asthma
• Steroid resistant asthma
• Emotional or stress related asthma
• Tobacco smoke related
• Drug hypersensitivity (salicylate sensitive, beta blockers)

 Allergic asthma

• 80-90% of all asthma sufferers have allergic asthma. Allergic asthma is triggered by allergens that are capable of causing an allergic reaction.
• Specific allergens include pet danders, pollens, dust mites.
• Others include pollutants, wood dust, smoke, irritant chemicals, viral and bacterial infections.
• Most of the childhood asthma is allergic type.
• Maternal smoking contributes to asthma or impairment of infant lung function.

 Non allergic asthma

 Asthma is called intrinsic when allergens do not play a role.

 Intrinsic asthma usually occurs at the age of 40, very rare in childrens.

 Intrinsic or non allergic asthma tends to be less responsive to treatment when compared to allergic asthma.

 Possible causes of intrinsic asthma include respiratory irritants are

• Perfumes
• Cleaning agents
• Fumes
• Smoke
• Cold air
• Upper respiratory infections
• Gastro esophageal reflux (GERD)