I have been taking neurontin for about 6 years since I was in a car accident and sustained a Traumatic Brain Injury (TBI). I take 900 mg a day at bed time. I was down to 600 mg for a while, but found I needed the 900 mg. there also was a time when I tried to not take this medication under the supervision of my doctor, but it did not work out. The anxiety and depression returned, so I began taking it again.
I dislike needing to take any medications and was once taking several directly following the accident and being in the hospital for 5 weeks. I found that neurontin really helps me and does not have side effects like some of the others did. I don't feel or know of any side effects.
Some of the other drugs I have been prescribed have been Wellbutrin and Abilify. The Wellbutrin was helpful, and it was difficult to stop taking it, but I don't feel the need for it now that I'm past the difficulty with anxiety and panic attacks that occurred for about after stopping it. The Abilify actually put me in the hospital. I developed numbness in my arms, sometimes tingling in my arms, and numbness with immobility of my hands. It was terrifyingly and it was my mom who researched online that these were possible symptoms. My doctors with a 3 day hospital stay did not figure it out. I stopped taking it and within a couple of days the issues subsided.
I am not a sufferer of PTSD, but am a supporter and I thought I'd share my personal experiences with these medications, however, I don't know it they would be any different for a sufferer. Everyone is different whether they have PTSD or not, so obviously there is no way of knowing if they will affect any two people the same.
I wish you luck in your pursuit of medications that work for you. I hope this helped some.