Opana ER 5mg is a prescription medication containing oxymorphone, a powerful opioid pain reliever. It is prepared for comprehensive release, which means it releases the medicine slowly over time. This is for people with moderate to severe pain who need continuous pain relief, not for short-term or occasional pain. It's important to note that Opana ER is a serious medication with risks of addiction, abuse, and slowed breathing. Due to these risks, it's only prescribed in certain situations. Always consult your doctor about any medications you are considering.