Hi Scoopy
Any opiate can cause depression when used over a period of time. For me, the stronger the opiate and the longer I used them, helped in my downward spiral into clinical depression. Non-functioning totally. I had had two bouts of depression previous to starting opiates, but these bouts were mainly caused by very painful circumstances.
I am a bit confused as to whether you are taking Vicodin or Norco? Either way, the opiates can cause depression. another thing that could be happening is that you are feeling withdrawal between doses. That is what has led many of us to up the dosages over time. Like mimi withdrawal eqch day.
I really think you should talk openly with your prescribing doctor and seek his advice. Opiate pain treatment can be a double-edged sword for sure.
Good luck
reach