Lamotrigine
"I've suffered with a constant severe headache for months. The medication didn't do much at 25mg or 50mg for me. I just went to 75mg recently. I see a little bit of improvement in the severity of my headache.  I also found that I have more energy in the day. It hasn't done much yet, but once I get to 100mg I'm hoping it will help some more. fingers crossed.."