Can Painful Joints And Seizures Be Considered Side Effects Of Oxycontin, Oxymorphone, Oxycodone And Demerol?

I have been on oxycontin and oxycodone for 8 years after the use of Lupron. It ruined my bones and joints and live in a lot of pain now disabled RN. my insurance wont pay for the oxycontin and provide alternatives Iam not familiar with. Levorphano Oxymorphone Exalgo and Nucynta ER. Iam terrified as I have had grand mal seizures from Demerol and Ultram. I have not heard of the above meds have they been around long and what about efficacy for severe pain.