Got your message. See your other post.
I had a persistant dry cough for about a year. I smoke so eveyone put it to that.
I went to an ear, nose thorat guy, come to find out I had a polyp on my voice box.
He took the polyp out, and no more cough? Just saying. It could be worth a try.
persistent dry cough can be caused by too many different reasons.
usually a problem in the lungs/air ways, anything including viral/bacterial/mold infections or asthma.
also heart conditions give persistent dry cough.
you need to consult a specialist, probably do blood tests, spirometry and chest x-ray.