I personally used to suffer worse than anyone i know, and no medications, prescription or otherwise, touched it at all. My eyes swelled up to the point i could barely see etc, time off work was the order of the day :\
Then my doctor introduced me to a steroid injection, which most GPs wont administer due to side effects, the main one being an unproven link between the injection and osteoporosis.
Given the severity of my hay fever, and that I am about at the lowest risk possible of osteoporosis anyway (young(ish) male, fit and definitely not malnourished), my GP saw it as a worthy trade off. Since having this, I have ABSOLUTELY no symptoms anymore. Last year, i had it slightly too early and it wore off midway through summer, and again hay fever knocked me for six. Had another dose of the steroid injection and within a day I was completely fine again.
definitely worth enquiring about, but finding a GP who will prescribe it is insanely difficult: This is the sole reason i haven't moved my GP surgery since moving back to Manchester, and have to drive the 35 miles to where I used to live!