After years of narcotic usage and the failure of anti-inflamitories to adequately control my back pain my doctor (mostly because of my adamant refusal to consider Oxycontin or Morphine or Fentanyl in any form whatsoever) started me on methadone to control my back pain in conjunction with Naproxen Sodium @ 800 Mg TID.
A nurse friend of mine has hinted to me of possible adverse effects of these two medications together. I spoke with my doctor about my concerns and he has told me that there is no concern whatsoever. My friend is adamant in her statement that there is some kind of adverse reaction of these two medications when used in conjunction together.
Does anyone know anything about this? I cannot find anything about it, and she refuses to be more specific because she cannot (or will not) be more specific . Something about giving medical advice without authorization. While I am sure that she is right in not being able to give out medical advice, I am unsure if she is right about possible reactions of these medications when used together.

Maybe it will reduce the effectiveness of one or both when used in conjunction?

Does anyone know anything about this? Or is she misinformed?

Any help will be appreciated.

Thank you,