However, they are often prescribed off label as a muscle relaxer and
/or sleep aid.
has a very short half life, and
therefore, I don't think it is the best therapeutic choice. Valium or Klonopin have much longer half lives (50-72 hours) and thus, provide a therapeutic benefit much longer.
Combining Xanax, Klonopin, or Valium with an opioid pain reliever can be a dangerous combination, especially if you are taking methadone for pain.