Anti-allergen pillow covers can help a bit if they're the good ones. My husband has two and I started snaffling one of his pillows all the time because I slept so much better with it!
Allergy can also be caused by a nutrient imbalance... but it's not much use to take vitamins when you're allergic to the vitamins. That was my problem for about a decade, until I got the acupuncture treatments.
It sucks that malnutrition can lead to allergy and malabsorption, and then that leads right back into more allergy. You can probably fix it if you catch it quickly enough at the first sign of malnutrition... not much of an option when living on welfare though. Oh well.