Dry cough??

My grandpa has had this really annoying dry cough since closing night. He had it a few weeks ago but it go away and came back ultimate night. Any herbal remedies that help for a dry cough?
Swallowing Pills?
Answers:    He have allergies more than likely unless his throat is sore or there is green mucus.

I hold not found one herbal remedy that worked and believe me Im th elast person to try pharmacuticals. I ended up geting the walmart brand allergy and throat medication. 2 LIttle bitty tablets and no more coughing.
How do I swot the 'breathing technique'
Check out for some home-remedies from here:
http://myblogonbeauty.blogspot.com/2006/...
http://myblogonbeauty.blogspot.com/2007/...
Real henna powder,!?
Lozenges that hold "Slippery Elm Bark" are very helpful. They coat the throat are are incredibly soothing. Check your local heath food store. Also honey in tea is impressively helpful.