If you are developing allergies, you might also want to try using as many products as you can that are totally fragrance free, lanolin free, formaldehyde free, etc. I am not affiliated with them, but I get shampoo, conditioner, sunscreen and other products by the brand name "Free & Clear." sold by Pharmaceutical Specialties Inc. I just order it online cause none of the local stores carry it. (PSICO.COM)
I use one set of eye shadow/mascara for about six months, then pitch it. Almay is good for me.
I also keep my pillowcase pristine clean - washed in fragrance free detergent and fabric softener, double rinsed, and changed every two or three days.