I have Asthma. Have had it since childhood.
It could be a seasonal thing. Things in the air etc. That affects me too. Seasonally.
Asthma, is a constriction of the airways, hence, breathing is impaired. To put it simply. Thus, inhalers will serve to reduce that constriction. Or it could be said, inflammation. Inflammation constricts the airways.
Nebulizer... what are you using in it?
There are many types of Albuterol and inhaler meds.
These medicines are "corticosteroids." Or Bronchodilators or anti-inflammatory meds etc.
When my Asthma is bothering me... (and keep in mind the acuteness varies), I wheeze, and/or cough and/or have breathing trouble.
There are many breathing impairment conditions.
To get a real conclusive diagnosis, you need to see a Pulmonologist.
And yes, your coughing can return or not after these meds. Because, you do not know what is causing it or triggering it.
With Asthma, there are many triggers. And it WILL vary for each person.
It is not a one sized shoe fits all. Nor in treatment.
Singulair, is used for a variety of issues... from Asthma to sinus problems to allergies. And it takes a few days of taking it, for it to then take effect.
Or maybe, you have a throat problem.
Or a sinus drip problem. This can cause, coughing as well. Because post nasal drip, causes the gag reflex, and the person then coughs.
I once had laryngitis, with similar symptoms you are experiencing. And it got worse... when I talked a lot. I was also sick with a head cold at the time.
So it can be a variety of things.
And basically, your Doctor does not know... what it is, or even if it is just a cold. And is doing a process of elimination...by giving your Singulair/nebulizer and seeing if that helps it.
Just as an example:
Here in Hawaii, when the winds are blowing a certain way... it also bothers some people and their breathing conditions. Because, it is basically the volcano "smog" that is blowing across the State. We call it "vog." It can really make some people just cough and cough.
So also, environmental things can also trigger coughing. And it is temporary, per that particular weather/wind patterns. It kicks up a lot of things in the air.
I get affected like that too. But at those times, it is not my Asthma, per say.
Does your city, have bad smog or bad air days???
Next: you are coughing... and it is exacerbated by talking and/or dust.
So, you did NOT mention, that it is your lungs, per say or that there is tightness in your chest/lungs. But you are coughing. It can be your throat or sinus post nasal drip too.
Coughs, arise from:
the chest/lungs, or
the Sinuses, post-nasal drip.
Or both.