Oxycodone, sold under brand name OxyContin among others, is an opioid medication used for treatment of moderate to severe pain. It is usually taken by mouth, and is available in immediate release and controlled release formulations. Onset of pain relief typically begins within 15 minutes and lasts for up to six hours with the immediate release formulation. In the United Kingdom, it is available by injection. Combination products are also available with paracetamol (acetaminophen) or aspirin.Common side effects include constipation, nausea, sleepiness, dizziness, itching, dry mouth, and sweating. Severe side effects may include addiction, respiratory depression (a decreased effort to breathe), and low blood pressure. Those allergic to codeine may also be allergic to oxycodone. Use of oxycodone in early pregnancy appears relatively safe. Opioid withdrawal may occur if rapidly stopped. Oxycodone acts by activating the μ-opioid receptor. When taken by mouth, it has roughly 1.5 times the effect of the equivalent amount of morphine.Oxycodone was first made in Germany in 1916 from thebaine. It is available as a generic medication. In the United States the wholesale cost per dose is less than 0.30 USD as of 2018. In 2016 it was the 54th most prescribed medication in the United States with more than 14 million prescriptions. Oxycodone has been a common drug of abuse. A number of abuse-deterrent formulations are available such as in combination with naloxone.