Very often it is more effective to treat the upper airway with cortison spray. Actually it is state of the art in treating hayfever to apply cortison locally, i.e. taking a nosespray with Mometason-17-(2-furoat) 1H2O 50 µg/per Spray (called "Nasonex" in Germany). This will help with your nose, eyes and sometimes with breathing. Then you can top it up with the occaisional loratadin/ceterizin or whatever pill. Eyes and nose are good with the expensive but long lasting (up to 8 hrs) Levocabastin-HCl 0,54 mg (called "Livocab" in Germany)
If you get asthma taking Budesonid 0,5 mg as a spray is good. (Rinse mouth after spraying!)
If your hayfever is really bad you could consider getting "desensibilized".
I have had really bad hayfever for many years and used to take pills only. When they did not help anymore I started the above decribed regime and am much better.