BIBLIOGRAPHY
http://www.ehow.com/about_5482301_side-effects-antitussives.html
http://www.youtube.com/watch?v=oh0nAyW5r5Y
http://www.youtube.com/watch?v=9zTFVmUK1gk
http://www.youtube.com/watch?v=d9ouk_46xA8&feature=related
http://en.wikipedia.org/wiki/Pharmacogenomics