· Reversable chronic obstructive lung disease

· Characterised by:

o Acute exacerbations

o Intermittent airway obstruction

o Chronic inflammation

o Hyperreactivity of airway to stimuli

· Symptoms

o Wheeze

o Cough

o Shortness of breath

o Chest tightness

o Severity varies over time (reversable)

· Complex disorder involving:

o Biochemical

o Autonomic

o Immunologic

o Infections

o Endocrine

o Psychological

· Extrinsic = allergic

Intrinsic = non-allergic