Okay, a couple things are going on here. First, both the Suboxone and the Gabapentin are going to cause drowsiness, so he may be fighting a battle against his medication. The Cymbalta should give a bit of a boost, but the Suboxone in particular is pretty heavy. If he only recently began the Cymbalta, then give it a few weeks to take root before going back the the physician to have the dosage examined.
Second, the Suboxone is affecting the pleasure centers of the brain, and essentially "coating" the receptor sites up there. The botXXXXX XXXXXne (I know it gets confusing) is that he will experience a decrease in general "happiness' while on the Suboxone. Drug addiction treatment may be necessary (hopefully, the talk therapy is incorporating this aspect) to address some of the issues of being hooked onto the opiates. If he is not an addict and does not have addiction in his family tree, then he may be able to wean off of the Suboxone and live free of the pain killers. If he has the genetic machinery for addiction present in his brain, then longer-term talk therapy and maybe a 12-step support group may be warranted.
Otherwise, the gabapentin may not be a long-term medication, depending upon how and why it is being prescribed. I would urge you to speak to the physician about the "Plan" regarding medical management so that you understand not only where the medication regimens are headed, but also what effects to expect.
And if shock therapy set him back, stay away from that form of treatment. Typically, that avenue is explored only when other medication treatments have failed. If he is just now on Cymbalta, then there may be options worth exploring.
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