Hydrocodone is not readily available in Western Europe where codeine is much more commonplace. Here are two links for your convenience. Different drugs that basically perform the same functions are available in different parts of the world. Hope this helps. God bless. 
http://en.wikipedia.org/wiki/Opioid
http://en.wikipedia.org/wiki/Opiate
I am not a dr. My statements are based on years of experience and related education. Consult with the professional of your choice regarding matters of concern.