Hello, and welcome back to Just Answer.
I'm sorry to hear that your cat is bothered by allergies every Spring/Summer. Cats can devleop the same sensitivities to pollen and other irritants in the air, when they are most prevalent during these seasons. Even if your cat is indoor-only, our homes are not 'hermetically sealed', so some outside air can get in. If your cat spends time outdoors, try to keep her inside more, during these seasons, if at all possible.
For your kitty, I would advise using a humidifier in the rooms she spends the most time in, as moisture in the air will cut down on her adverse effect to the allergens, and also, discuss with your vet if she can be given an antihistamine like Chlor-trimeton, as needed. Here is more information about this medication: Chlor-trimeton
You don't have to buy the brand name, as most drugstores carry their own, generic brand, which is significantly less expensive and contains the same active ingredient. I'd start with 1/4 tablet once a day and see how she does. If she needs more, try 1/4 tablet every 12 hours. If she's difficult to pill, you can use Pill Pockets Treats by Greenies (available in pet supply stores) or crush the tablet finely with the back of a spoon (it's pretty soft) and mix with a small amount of canned food you know she likes.
I hope all will be well with your kitty and she finds relief from her allergies this season!
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