Benadryl Extra capsules (1 per 8 hours I think).
Just don't over take anything, only take them when you really need it or if you know you are going to need help throughout the day e.g. you're going out somewhere and you don't want to be affected, or you will get used to them and they wont work as well. It's also a good idea to check the pollen count everyday on a local weather site or something.