Originally Posted by FrazzledFairy
I too have been switched to the Opana ER. However, I'm not finding any relief w/it and I know at 30mg, I should - well, I think. Is there any possibility that the med. is old or something? Anyone else found Opana ER to be ineffective? I'm confused. I've read great things about it.
Oxymorphone has a very low oral boiavailability, around 10% which is very low. This means when you take Oxymorphone orally you don't absorb much of the drug. Obviously some people probably absorb more, but it would still be pretty low for the average person. Don't get me wrong Oxymorphone is a very, very, very, potent drug when used intervenously in a hospital setting. But orally not so much, but for some people it works fine. There is a nasal spray in the works using oxymorphone for breakthrough pain, but I am not sure how much more absorption there will be, but it should be fast acting intranasaly.
Oxycodone on average is very well absorbed at around 80% absorption rate. That is one of the reasons why it works so well orally. Also one of the reasons people started abusing Oxycontin, starting out taking it orally because of the high absorption rate.
Methadone also has a very high absorption rate when taken orally.