Oxycodone Liquid, also known as oxycodone hydrochloride oral solution, is a prescription medication used to treat moderate to severe pain. It is an opioid analgesic, which means it works by binding to opioid receptors in the brain and spinal cord to provide pain relief. Liquid oxycodone is typically prescribed when other non-opioid pain relievers are insufficient or when patients have difficulty swallowing pills.