I've been tried on Paxil, Impramine, Wellbutrin, and Buspar myself. They all made me much worse. One sign of problems I realize now was stomach upset after taking them especially Buspar. My head would hurt. But the doctors insisted I had to take it and must go off Xanax.
I've had PTSD, OCB, and General Anxiety Disorder all at the same time. I got rid of two of the three. The G.A.D. is due to a neurological dysfunction that not that much is known about except for me it's permenant. I had PTSD from some bad things that had happened over a 10 year period in my life. I developed Obsessive Compulsion as a compensation for losing my ability to concentrate. The GAD is Sensory Processing triggered involving my Inner Ear as well as Optic processing. All three came together at one point. That's one reason SSRI's can be dangerous to some persons with neurological issues. In such cases you want to dull sensory impulses not enhance them.
My wife whom the Serotonin Syndrome happened to {I eventually diagnosed it after about the 4th day of it not the doctors} has taken Xanax since 1985. The PTSD in her in part came from a dentist who had overdosed her on Mepraghan placing her in hypothermia. This was for a basic extraction. BTW she's an incomplete quad.
The trick with Benzo's is in a small frame patient use .25mg 4 times a day. On a larger patient use .5 mg 4 times a day. These patients should be very light drinkers with no previous addiction issues. Here's why. It is a low dosage but stays in the bloodstream 24/7. That stops rebounding and craving issues. Now what really screwed me up was when they had me on SSRI's and 2mg of Xanax 2 times a day. I was yo-yoing from it like crazy but in hind sight it likely kept me from going into Serotonin Syndrome too. I got a good doctor who knew how to treat what I have & went off all SSRI's and went on Xanax only. Life improved from that point. Actually most days now I take 2-3 doses. The Xanax also controls my Myclonic seizure activity. With this type of GAD you can toss the stuff written on Panic Attacks and Anxiety Disorders out the window because it won't work.
Clarification on post 10. My wife developed Serotonin Syndrome from taking Trazadone and Zoloft as prescribed. She was also thankfully on Xanax at the time or it would have likely killed her.