I have this sensation all the time. Doctor told me I have Gerd but even after an endoscopy there was no evidence of it and I never get heartburn, avoid spicy foods and drink decaf coffee. This first began when I developed excess mucus in my throat and to date nobody has provided a cure or a real explanation as to what causes it. At least once per day I have trouble clearing my throat. I've now had it for years and have come to accept that I'll probably have to live with this from now on. I'm 72 and eat properly and exercise daily. I have the occasional glass of wine and a beer now and again.