I am just wondering if anyone has had any bad mental side effects from this drug? I started taking it a little over a month ago and started doing things I would never do.I was prescribed this medication after being on Vicodin ES for almost 2 years due to multiple surgeries. My doctor told me that it was a "break through drug" and was easier to wean off then the Vicodin. The initial side effects were feeling sick, dizzy, like I was not myself... and then I get extremely angry/intense rage for absolutely no reason. I have stopped taking nucynta but would like answers to why this medication does this and why this is not on the side effects list. I feel this drug is extremely dangerous.