How To Treat Itching Sensation In Throat While Breathing Through Mouth?

Everytime I breath through my mouth while out in the cold air it feels like my throat is itchy and I m choking on spit and it sends me in to a coughing fit. I ve tried antihistamines, prednisone and albuterol, but can t get rid of this sensation....any suggestions? Lungs are also clear.