Allergens cause mild sneezing and coughing on one hand and can lead to a severe reaction on the other. The disease asthma, can be of different types and severity. It ranges from occasional tightness of chest and wheezing to severe shortness of breath and decreased oxygen levels in the blood. Information on different types of allergies and measures to check them are dealt by this book. This book also mentions that asthma can be managed and treated with the help of a proper diet, precautions and medication.