According to Dr. Hu Xi-Shu, the main cause of coughing is the invasion of phlegm-rheum, which should be treated by warm transformation, descending counterflow, and calming (the cough). 
When treating coughs in general, there are numerous formulas to choose from, some may even go so far as to say that there are thousands upon thousands, but Dr. Hu would most commonly use the formula Ban Xia Hou Po Tang (Pinellia and Magnolia decoction). When asked about the reasoning for this, he would answer that in the Jin Gui Yao Lue’s (Essential formulas from the golden cabinet) section on coughs it is said that there exists an intimate relationship between phlegm-rheum and coughs, and that many cases are in fact due to the upward invasion of phlegm-rheum, which causes qi counterflow with an inability to descend. In regards to the treatment of phlegm-rheum, it is said in the Jin Gui Yao Lue,
“In phlegm-rheum diseases, one must harmonize with warm medicinals”.
This is the most important main treatment principle when treating phlegm-rheum conditions, and in addition is the main treatment principle when treating coughs. When adapting this principle (in the treatment of coughs), one must also use appropriate medicinals to guide the treatment downwards in order to descend (counterflow). Clinical practice offers us many opportunities to promptly offer a resolution of this symptom.
To read one of Dr. Hu’s cases utilizing this formula, click here.
Eran Even, Ph.D., Dr. TCM. 
Hey Eran,Eric Grey here – we met at the Zeng Rongxiu conference… wow, was that only yesterday? Anyway – just saying I found you, I'll be reading, and we should definitely be in contact by email to help eachother's sites flourish. I look forward to seeing you at another event, another time. Until then… cyberspace. :)Erichttp://deepesthealth.comeric@deepesthealth.com
Hey Eric,Thanks for checkin' out the blog, much appreciated.I just got back from a long day driving back north. Happy to be home, but sad the conference is done. I could have easily done a few more days :)Was great meeting you, and we will most certainly keep in touch.I will also add a link over to your fantastic blog/forum.Talk soon my friend.Eran
Cool! One thing I noticed about your blog is that I can't figure out how to subscribe to posts. The normal RSS option is not available in Safari, and I don't see a link in your sidebar anywhere. Are you signed up for Feedburner? I'd like to get notification when a new post comes up. Looking forward to learning more about Hu Xi-Shu!e
Being the not-so web savvy guy that I am, I'll have to look into that. Thanks for the heads up.Stay tuned for the Hu Xi-Shu extravaganza! 🙂