bipolar disorde
"A lot of people seem to really like neurontin for bipolar disorder. My experience unfortunately was not that great. I took it as an add-on to lamictal after I had a couple manic outbursts from taking lamictal alone. 

Gabapentin initially helped with anxiety symptoms (mental + physical) and really helped calm me down, help me sleep, etc. However, it dragged me back down to severe depression. I couldn't feel good about anything on it. Even when my doctor and I experimented with different dosages for lamictal and gabapentin, I couldn't find a good balance. Mostly I just experienced depression. 

I'm being taken off gabapentin soon. I really wanted this medication to work, but the benefits did not make up for the negatives."