1 Some dog breeds, such as Chihuahuas, are better for people with asthma and allergies
Reality: it’s the protein in the pet’s saliva, dander and urine that causes allergies, not the hair. Since all dogs have dander, saliva and urine, there are no particular breeds that are better for people with asthma and allergies.

2 Asthma can be cured
Reality: there is no cure for asthma. However, with the proper diagnosis and treatment, people with asthma can lead normal, active lives with little disturbance to quality of life.

3 Moving to a different area will cure asthma and allergies
Reality: moving to the coast or an upland area may relieve allergies for a few months but new allergies – to new local plants, for instance – can develop within a short period. Moving house does not offer an escape from allergies and asthma.

4 Children outgrow asthma
Reality: asthma is a chronic state of hyper-responsiveness. Some children have asthma symptoms that clear up during adolescence, while others worsen, but the tendency towards over-sensitive airways remains. Unfortunately, there is no way to predict a child’s clinical progress.

5 Allergies are a harmless problem
Reality: allergies are serious and should be treated effectively. Left untreated, they may lead to poorer quality of life, including impaired sleep and learning ability, and absences from school and work. Untreated allergies may also result in chronic respiratory problems, such as asthma and sinusitis, and skin disorders, such as eczema and urticaria (hives). Some allergies, such as those to foods, drugs and insect stings, may even lead to life-threatening anaphylaxis – an allergic reaction affecting major body systems that can be fatal.

Source: http://www.readersdigest.com.au/five-allergy-and-asthma-myths