Buy OxyContin Online with Careskit review . Oxycontin is an opioid pain medication. An opioid is sometimes called a narcotic. OxyContin is used to treat moderate to severe pain that is expected to last for an extended period of time. OxyContin is used for around-the-clock treatment of pain. It is not to be used on an “as-needed” basis for pain.It should be administered every 12 hours.