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 your 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.
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 disorders (like depression).
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.
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.
If $$ is a super-big issue, you might want to consider contacting your local Community Mental Health Center. These tend to offer free or greatly reduced cost mental health services, including therapy and/or med management, depending upon your ability to pay.
Finally, you make note of your son's substance use. While it is possible that there may be an underlying substance abuse problem here, in all likelihood, your son is doing what many people his age do - uses (perhaps overuses) substances recreationally and/or to self-medicate. The vast majority of people in their 20s overuse substances and then "settle down" and revert to normal social use. If, however, your concerns are significant - I would encourage your son to consider speaking with the CBT therapist about this issue.
Thanks. I hope you're well and that this was helpful.
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