Opana ER (generic: oxymorphone) is a prescription medication used to treat moderate to severe constant pain. Opana ER belongs to a group of drugs called opiate analgesics. It works by changing the way the body responds to pain.

This medication comes in tablet form. It is usually taken every 12 hours, on an empty stomach. Swallow Opana ER tablets whole.

Common side effects of Opana ER include nausea, constipation, and dizziness. Do not drive or operate heavy machinery until you know how Opana ER affects you.