Not together, but separate and years apart.
Keeping in mind that everyone reacts differently to medications, and it can be hard to find a med or combo of mess that works. Especially since there isn't an exact medication to treat PTSD, it's a best guess based on symptoms and chemistry. So if this doesn't work, don't be discouraged.
Personally, I'm not a candidate for any ssri and Zoloft was the worst of them all. It incited an intense urge in me to violently to hurt anyone who came near me. It also made my already present suicidal thoughts to go into overdrive! I couldn't control my thoughts or reactions at all. I actually ended up hurting my son while taking Zoloft. Not seriously, but I was scary!
Gabapentin can be a lot for some and really helpful for others. I never got past 200mg. For some reason my system couldn't tolerate it, it caused massive vertigo. Couldn't move! It left me basically sitting in one spot at all times. I tried this med for over a month, and my body never got used to it, it only got worse. But I've had friends who found it very helpful for their symptoms. I've heard it can be very difficult to warn off of(have one friend who just started tapering her dose because of health issues it was causing) and she's having a pretty tough time.
Either way, hopefully you can find something that works. Emdr was very helpful for me! So I understand to desire to try.