low sodium

Has anyone found that they have had a problem with recurring low sodium? My surgery was in April 2002. I had RNY.
My sodium level keeps dropping. My prescription drugs for depression and anxiety are being blamed but I'm starting to wonder if maybe my gastric bypass may be playing a role in this.  I have been on anti-depressants for years and my sodium problem has just recently started.
Does anyone have any thoughts on this problem I am having?
Thanks,
Cheryl