Roxicodone is used to treat moderate-to-severe pain, insomnia and opioid addictions. It works by affecting the brain and spinal cord to decrease the messages that are sent to your brain and limbs by your nervous system. A side effect of this medicine is sleepiness, which can make you or someone else around you less alert than normal. If you have been prescribed the medication for pain relief, you may notice that your body reacts positively to the medication. The symptoms of opiate withdrawal can occur if you stop taking a dose of this drug as prescribed or have taken it improperly.