Are you a smoker edwin? If so id say this is the problem. If not then it remains a mystery. Do you work with chemucals that may be irritating you?
It appears that when you speak and start to cough, the throat is aggravated by an irritant. Coughing is the body's natural response to get rid of irritants.
The voice needs to be looked after like any other organ. Keeping it lubricated by drinking enough fluids (not alcohol), avoiding irritants (not always possible), not shouting, but knowing how to throw the voice without straining the larynx and resting the voice.
It appears that there is an air irritant that is irritating the pharynx making you cough. It could be dust, cigarette smoke, chemicals, perfumes, animal dander and so on.
Have a bottle of water with you so that you can have a drink when you notice an irritation in the throat. Drink plenty of fluids so as not to get dehydrated.
By sucking a menthol lozenge you are helping by soothing the irritation.
Get your throat examined to rule out any underlying problems.
Best wishes.
you need to see a Dr a dry cough could be mean alot of things. Bronchodis, Cancerous, HIV
long term cough is a not a good sign