I think it is possible to come off fentanyl without going into a rehab. Talk to your doc and get patches that cut your dose by whatever your doc thinks is reasonable....or what you feel is tolerable.

I have gone off fentanyl more than once and had no real issues....just the usual stuff, restless leg, sneezing and flu like symptoms over a few days.

I don't want to advise any one, since, we are all different.

Klonopin is another story. That withdrawal truly makes on feel like one is dying and it lasts a very long time.