I recently had an overnight sleep study with results showing that I have 0% stage 3 & 4 sleep. The sleep dr., a pulmonologist, said that this is out of his field and referred me back to my primary. My primary has prescribed Elavil. I don't mind trying it, but I don't believe that it will really do the job. Dr. Nancy Klimas has written that Xyrem is best for inducing stage 3 & 4 sleep. Has anyone used Xyrem or had positive results with the class of anti-depressants that Elavil is in?