I had been taking 5mg of Lisinopril for almost 10 years with no n...

I had been taking 5mg of Lisinopril for almost 10 years with no noticeable side effects (at least not ones the dr. would consider), I have gained weight and attributed it to age or eating habits, I started snoring and attributed it to weight gain, my stomach feels bloated every night (my wife blames my eating)... In any case, after pharmacy error in Nov. when I took 40 mg instead 5 for one month by mistake, the Dr. brought me down to 20mg instead of the original 5mg since he said 5 might not have been doing anything. After 2 months on 20mg I started with a persistent dry/tickle cough in my throat which I thought was part of the winter flu. I never had any other flu effects, however, now 3 months later there is not a day that goes by without the cough. Finally, a new dr. has taken me off this family of drugs. It has only been a week. Cough persists. When should I expect it to go away, and what can I do to help it along?