My Husband Has Had A Surgery For A Neck Fusion.

My husband has had a surgery for a neck fusion. He also has some back issues and is waiting for surgery on that as well. His pain in his neck is better but still hurts and his back hurts all the time. He has been on Gabapentin for 1 year. 300 mg 3 times a day. He has frequent headaches and short term memory loss. His doctors say that the Gabapentin would not be causing this but articles that we read and the list of side effects specifically mention memory loss. Can you please advise if he should wean himself off of it and see if his symptoms improve?