100 Days Cough

I hope I haven't gotten the 100 Days Cough again. I had the mysterious illness well known in China and Hong Kong -- everyone who saw me said, "You have the 100 days cough." -- but unknown to US doctors even those specializing in infectious and tropical diseases. I have been sick for the last few days with a nagging cough. Luckily, I found some Hall's cough drops that have a "refreshment level" of 4 -- as scientifically shown on the packaging. They make the cough go away while they last. I would like the refreshment level 5 -- the maximum, but can't find them. Maybe they are a controlled substance.