Buy Oxycodone Online For Incredibly Manage Chronic Pain. A powerful opioid analgesic, oxycodone is mostly used to treat moderate to severe pain. Because of its great potential for abuse and dependence, it is categorized as a Schedule II controlled substance. By attaching to opioid receptors in the brain, spinal cord, and other parts of the body, oxycodone modifies pain perception and induces sensations of relaxation and euphoria.