The concept of environmental control therapy is quite simple, control your allergies by avoiding allergens and triggers. It requires a great deal of discipline on your part as it is much more complex than merely swallowing a pill or getting a shot.
Means and methods of environmental control include:
Daily vacuuming
Running a HEPA-filtered air purifier in your home
Encasing your mattress and pillows with protective covers
Washing bedding in hot water on a weekly bases
Frequent dusting
Installing hard-surfaced flooring rather than carpet
Keeping pets outdoors
Your environmental control therapy plan will depend largely on your specific allergens. The overarching goal is to limit exposure to your environmental triggers.