Seasonal allergies can vary from year to year, due to your health status and the particular environmental details. Weather sometimes makes for a bumper crop of ragweed, for example!
Don't forget about the neti pot. Saline rinses a few times a day during allergy season can make a difference.
Also helpful for me has been Quercetin (a flavanoid), but there are some questions about using that in pregnancy, mostly due to tests on rodents given obscenely high doses. So I dunno. It's one of those things that won't do much immediately, though, and seems to work best when started before allergies get too bad.
I had terrible, terrible allergies last fall, when I was still having severe first trimester nausea, and ended up using NasalCrom. It's a nasal spray, like Flonase, but Category B and over the counter.
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