One way to treat is through nebulization. In this the drug goes directly into the lungs just like inhalers.
Rotacaps is another such method. You can discuss this with the asthma/COPD specialist. The medicines used can be asthalin, trebutaline, steroids, ipratropium bromide, and chromolyn sodium amongst a few options available. You will have to keep the house, bed linen etc dust free. Check for molds at home—under sink, bathroom, toilets, drains, damp wall, under carpets etc.