Dopamine is a chemical in your brain released as a "reward" in response to behavior that the body wants to encourage, so getting food, having sex, these all produce a dopamine release. No dopamine = no sense of reward, so instead of feeling great that you got that promotion, got an A on that paper, smacked the game winning homerun, or even did something as simple as left your room and sat on a hillside on a sunny day, you just dont care
Wellbutrin, if you wish to go the pharmaceutical route. Or you could try consciously put effort into enjoying life. People tend to be detached emotionally from the little things that make life worth living. It seems in this day and age we forget where we come from, and what makes us human.
Id suggest paying more attention to things, relaxing, trying to clear your head a bit, and doing things you really love doing.
Yeah, at this point you're essentially asking how to cure depression, and there's more suggestions for that than there are people on this thread. I mean there are the special lamps for people who dont get enough sun, you can go talk to someone (ie, thereapist, psychiatrist, whatever) which I'm sure you'd have to do anyway if you go the pharma route - or your friend, whomever, just easier to write in the 2nd person.
It's actually funny that thsi topic came up today, i've just started reading "how we decide" which seems to be about the actual mechanics behind the human thought process. And if I'm reading it right, which I very well may not be, an actual dopamine absence would mena that your friend was completely unable to learn from his mistakes. Not mistakes like "his constant need to make himself indispensable only leads to his dating woman with issues who eventually take him for granted, perpetuating his lancelot complex" etc, I mean mistakes like "hmmm, sticking my finger in this electrical socket shocked me last time, lets see about now ... BZZZZZT! ... ok, but what about this time..." As in, no reward, no punishment, no incentive to learn from our mistakes
then again that coudl be an extreme case resulting from a lack of ANY dopamine, not just a general insufficiency. But hey, like i said, i could have that whole thing wrong
Wellbutrin is supposed to increase the action of dopamine. But results vary tremendously between individuals, and it's not common for any anti-depressant that I know of to do a great job curing anhedonia or apathy. It's certainly worth a try for a guy like this, but I wouldn't be surprised if it did not seem to do a whole lot.
The problem with a guy in this situation, or anyone with major depression, is that there IS nothing you really love doing. Loving doing things depends on a healthy brain with balanced neurotransmitters. Without that healthy brain, everything seems pointless and nothing pleasurable. It is truly hard to imagine if you have not experienced it.