I take Piriton in liquid form and it does the trick. My main problem is a running nose, I still get itchy eyes but its manageable, whereas streaming nostrils are hellish. Otrivin nasal spray is very good too when all else fails, but you have to use nasal sprays and decongestants sparingly.
Rarely, I will roll up tissues and put them into my nose, end up looking like Rudolph the Rednose Walrus with snot-soaked, two-ply bungs for tusks. That actually really helps, but its not practical. A nice cold shower can provide brief relief too.