I have struggled with auditory, visual and olfactory hallucinations (flashbacks) most all my life.
I was diagnosed with (Complex) Post Traumatic Stress Disorder and was placed on Seroquel and Effexor early on in my treatment process. Later I was taken off those and placed on Wellbutrin. Now I'm not on any medications.
I don't think the medications had an effect one way or the other.
I do know that getting away from the abuse I grew up in, and by making significant lifestyle changes that reduced the amount of stress in my life did though.
I still have them occasionally, but not near as many as I did, and they don't disrupt my life as bad as they used to. It's more like a gentle reminder of what can happen to my mind if I don't take care of myself.