Gabapentin
"My husband has been taking 3600mg of gabapentin for about 4 or 5 months now. He has been on a lower dose (1800mg) in the past. It has helped lessen his nerve damage pain but still in pain.

I have noticed severe behavior and mood changes. He has become very irritable, aggressive, moody, depressed (confused, numb, lost), lower back pain (as if his back doesn't decompress when he lays down), trouble sleeping, suspicious and distrust. This medication may help nerve pain but is a huge relationship killer."