I have a hack as well but only in the middle of the night. When ...

I have a hack as well but only in the middle of the night. When I first started taking Lisinopril, the cough was throughout the day but not as disruptive and some have described. The cough abated but never completely went away - stuck around to wake me every night. Now, it seems to be getting worse as it has twice occured during the day. Is anyone else experiencing this sort of intermittent hack? My doc says he doesn't think it's the meds cuz I'm not hacking all day long. Thanks