I have LSN and have for all my life (72 years). It has gotten progressively worse over the years and is very bad by now. Following every possible treatment (including a tonsillectomy) years ago, and test after test (at National Jewish Health (Denver) for seven days straight, it was concluded that I have LSN....an "over sensitive larynx".
At this time, the only POSSIBLE medication for LSN that I have found through research only that does help is called Gefapixant (LYFNUA). Studies showed that it helped 85 % of the patients (subjects in the study).
Unfortunately, it is ONLY available in Japan at this time. Merck Pharmaceuticals did a study on it and the FDA did not approve it (March 2022) due to a side effect of a metallic taste left in some "subjects" mouths. I have been in contact with Merck and two different people there have told me that there are "documents" saying that they will revisit their request. Hopefully, this will happen soon!
My triggers are any odors (good or bad) and cold drafts. I ALWAYS carry a thermos with hot, hot water, and Ricola cough drops. I wear knit scarves a lot. When I go into a store and cough, of course I wear a mask, and I just tell people who give me mean looks, "I'm fine. I have asthma" ....which I do not really have! Lakarol lozenges, (order on Amazon) under my tongue, helps to keep my throat moist. A voice therapist told me to exhale slowly through the nose.
Those are my suggestions. I have researched this for many years (before the doctors or anyone knew what LSN was). Now that the doctors have labeled this, we need to hope that Gefapixant or another medication or procedure will one day be available in other countries.
Perhaps we can all telephone Merck Pharmaceuticals and pressure them to revisit their study in hopes that the FDA will soon approve that medication!
Ronda