Gabapentin mood swings

Hello...Was taking 300mg of Gabapentin for prolonged muscle soreness and anxiety and 50mg of Pristiq and felt pretty good except i was itching bad so we quit Pristiq and doubled Gabapentin to 600mg a day.
That was 2 1/2 weeks ago and my itching stopped but i have become really moody and irritable since.
So we are on day 3 of going back down to 300mg of Gabapentin and 25 mg of Pristiq with Clariton for itching.
Was wondering if anybody else became moody and irritable on Gabapentin?
It seemed to start right at my dose increase so i am hoping backing down my dose is the ticket.
Thank you