bipolar disorde
"I've been bipolar for 20 years. I'm a scientist, when I'm working. Lithium has always been helpful but is not so great for depression though it does help if you take it a while. I finally started lamotrigine about a month ago. Lots of friends and professionals I know and trust said I should. I was skeptical since drugs tend to be bad news. After just a month (I titrated up quickly, so I've been on 100 for 2 weeks. probably best not do that there's a fatal skin disease you can get) my low level depression feels better. 

I'd say it's genuinely beneficial for bipolar depression. A little dizziness but not so bad, and it fades. My friends say there's no evidence that more than 100mg or 150 helps, but it could increase side effects. 100 is good"