Does anyone have hay fever tips (for Berlin) outside of getting an air purifier? do I have to live with the windows closed at all time?

London, Brooklyn, Portland were all fine for me, but pollens in Berlin springs are the bane of my existence. :(

@muan it's been better for me this year, I wonder if my body has gotten used to it. There's also sprays you can buy over the counter, that has worked well for me as well. But it was never too serious for me.
@chris oh that lessens my anxiety somewhat. My reactions have been worsening but we will see how it is this time around. Thanks!