Ironically as I started to read this I was holding my Oxycodone vial and contemplating taking one. And now I am. At least my impulse is because of post-surgical pain, and hopefully will fade with the pain.
It's not the drug that feels good; it's the respite from pain, and that only by contrast. Lacking that contrast, the drug induces only a profound, if temporary, physical and emotional numbness. It's not pleasurable, because it's not anything; it's as close as anyone alive can get to being dead. Unless that's something you want, you need have little fear of prescription opiates - just as much as is consistent with a healthy respect for, and avoidance of, the risks that come with their benefits.