Suggest Treatment For Post Nasal Drip

I HAVE LIKE A RUNNY NOSE FROM BACK OF NOSE BUT FEELS LIKE A RUNNY HEAD LIKE A COLD IN THE HEAD. I SUFFER FROM RHINITUS HAD A COLD TWO WEEKS AGO AND ALOS BEEN ON LISPINORIL SINCE NOVEMBER 5MG BUT THAT SEEMED OK KEEP THINKING MIGHT BE TABLET OR DO YOU THINK THE ACCESS DRAINAGE IS A VIRAL INFECTION BOUGHT ON BY A COLD. i HAVE TRIED LOTS OF NOSE SPRAYS AND ANTIHISTIMINS. ANY IDEAS