@VD15 Technically I have allergies too, but it doesn't get bad unless I basically go to a remote village in the middle of summer and live there for a few days. Cities are sterile enough for me that it's rarely an issue.
And when I would get the nosebleeds, there was no correlation with an allergic reaction or even a cold.
I don't even know why they stopped. I guess, at some point, whatever blood vessels were causing problems became more sturdy as I grew.
Hope your allergies get better though.
@alyx I get one of these basically any time my allergies flare up. I had lighter ones when I was a kid until I fell flat literally on my face one day and since then they've always been super heavy.