mg OxyContin OC 80 mg is a prescription medication generally used for unbearable pain in chronic conditions. OxyContin OC80 mg green pill is an opioid analgesic that works by altering the way of brain and nervous system respond to pain. Here, OC indicates that it is the original version of OxyContin with an extended-release formulation that can relieve pain for 12 hours. OxyContin is a higher dose containing 80 mg of oxycodone hydrochloride, appropriate for the patient who requires continuous, long-term pain relief. You should keep in mind that OxyContin is an extended-release version of Oxycodone, not the same as it. Also, consider Oxycodone VS OxyContin Differences and similarities to avoid the combination.