I, too, suffer from allergies (although mine is year round). I am allergic to everything: pollen, mold, dog hair, cat hair, feathers, grass, dust (like, where can I possibly go without dust?) Anyway, I've had these allergies for the past 15 years or so. I also suffer a mild case of allergen-induced asthma--nothing serious, but definitely more noticeable during certain seasons. Oh, I'm also on 3 different types of allergy medication: Zyrtec, Singulair, and Astelin.
There are definitely things you can do to help with your daughter's reactions to allergens. You should be aware that once a person has allergies, s/he will always have allergies. The allergies themselves may lessen over time, or they may change completely (especially if s/he relocates). But I agree with the other posters here, the first thing you should do is have your daughter tested to determine what type of allergens she reacts to. Saying "pollen" or "grass" or whatever isn't enough--there are so many different types, and there may be some she's not allergic to at all. My allergies started when I moved to an agricultural area--where a lot of peat dust is generated.
The second thing is to remove as much of the triggers as you can. Removing the poor dog (if she's allergic to dog dander), or dehumidifying a room (if she's allergic to mold), or removing carpet (dust, pollen, etc.), will greatly alleviates the symptoms. Air conditioning units seem to intensify my reactions, so I never use it. I have replaced them with swamp coolers--they don't work quite as well as far as cooling a room down, but they're nice on my system.
Other considerations: "allergy relief" products such as dust mite covers on the mattress, or feather-free pillows, might be helpful. Even the simple things like washing my face before I go to bed at night really helps lots. Actually, her nighttime activities will indicate how well she responds in the morning, since those are usually the peak times for allergy reactions. I've also reduced my dairy consumption quite a bit, since dairy apparently contributes a lot to the "snot factor" (according to my allergist).
The third thing, if you can afford it, is to place a HEPA-filter air purifier in her room. This isn't your average air purifier. The HEPA filters are more costly than most because it's really the one that can truly filter out the allergens (they are a lot smaller than most things that float around). I bought an Austin Air for my bedroom and it seems to work fairly well. It's also more quiet than the others--emitting a nice "hum", which generally puts me to sleep. Plus, their filters are good for about 3 to 5 years, depending on usage. I've included a link here for you, if you're interested in checking out allergy-relief products. (I did not purchase anything off this site, but I think it's a good resource to peruse.)
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