I'm sorry that your son is going through a rough patch right now. It seems that he's tried a number of things to help his situation. I certainly wouldn't diagnose over the internet (neither appropriate nor ethical), but I do have some advice regarding the proper treatments for depression (and anxiety).
Research has consistently demonstrated that treatment plus medication is more effective than medication alone or treatment alone for depression and/or anxiety. Further research has shown that Cognitive Behavioral Therapy (CBT) is the most effective form of psychological treatment/intervention - particularly in dealing with mood and/or anxiety disorders.
A licensed psychologist/psychotherapist with specific training in CBT modalities would be able to address your concerns. I would encourage you to find a licensed mental health professional with whom to work, employing CBT. Be sure when you speak to a possible licensed mental health professional that s/he employs CBT techniques - not just "influences from CBT" or "an eclectic approach."
With regard to medical treatment, many/most physicians appear to begin with a Selective Serotonin Reuptake Inhibitor (SSRI) to treat anxiety. Because I am not an MD, it is beyond my purview to address medication concerns, however. It appears that he is currently using an appropriate SSRI medication.
Again, the mantra of years of research says: medication or treatment alone is not as effective as both working in tandem. Some research has also indicated that insight-oriented talk therapy is counter-productive with some forms of mood and/or anxiety disturbance... it actually exacerbates the condition(s). So, seek out a CBT therapist who will provide targeted, efficient, and effective therapy - not someone who signs you as a "lifer." If you're going to a therapist for years, something about the therapy isn't working.
Your psychiatrist *may* know of a CBT licensed mental health professional. Please make certain, however, that they employ CBT practices.
==> There is a possibility that you son may have a form of dysthymia - which some consider a "low grade" form of "constant depression." Others have described this as a "characterological depression" meaning a long-standing tendency to view the world pessimistically or "depressively." Again, no diagnosis can be made over the internet, but this is a possibility. Appropriate strategies to address this, again within a CBT model, would be to provide training in now "non-depressives" view the world and appropriate actions to take to stay engaged and functioning in the world.
==> The second point to make, briefly, is that your son may be experiencing the typical angst associated with wrapping up his final year(s) in college. This transition into true adulthood is stressful for many and may require some "pulling away" in order to rally his emotional resources. It is also important to note that this is also a time when he will truly sever some ties with his childhood (which includes family) in order to gain independence and his own identity. Please be patient with him as he does this... it may be painful for both of you... but a necessary part of becoming an adult.
I wish you and your son all the luck! Thanks. I hope you're well and that this was helpful.
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