I Was On Percocet, And My Doctor Recently Changed Me

I was on Percocet, and my doctor recently changed me to hydrocodone, the reason is he said that the medical association has put out a warning about opioid addiction and overdose. I have chronic pain due to my sciatica condition for 7 years. The hydrocodone does not work. Is there a problem? http://www.healthcaremagic.com/web/images/ui/consultNew.png