I Am An Allergy Sufferer Living In Dallas. But This

I am an allergy sufferer living in Dallas. But this summer has been particularly difficult. I struggle the most (coughing, drippy nose) when i go to bed. Like clockwork, an hour after I fall asleep, there is coughing and tremendous drainage. I am tired of going to bed with a towel and sleeping the rest of the night in a recliner. What can I do? Please help.

Thanks! Rick