I don't know, I guess people are different, but I have been taking several 7.5 mg percocets a day for years and when I developed a sensation of sunburn all over, several people on here, including Mrs. D., suggested that the opiates could be to blame. They do rarely cause allodynia, but usually at pretty high dosages. I just stopped taking them, and while my pain levels were higher and the burning seemed unabated, I had no withdrawl or addictive issues. After a trial of several weeks I went back on them as I function better with significant pain relief. I am not really concerned about dependency, I am dependent on Miralax for my quality of life as well as my opiates, but it was good to know I could quit if I needed to.