I Read two Books. One was the Chronic Cough Inigma & the other was Killing Me Softly. It recommended low dose Amitryptaline (spelling?). It did not help. My doctor said she wanted to try Nortryptine 50mg working up to 100mg. My chronic cough of 8 years, said to be caused by acid reflux, stopped almost immediately. It was amazing, like someone flipped a switch.
Wish you the best.