I'm on Lamictal for seizures, but I started noticing that after my dosage got up over 350mg my headaches started getting better. So many other med changes were in work that I have no idea if the improvement was due to something else (like my Diamox dosage was doubled). Lamictal isn't FDA approved for headaches/migraine prevention, but my neurologist told me some doctors use it off label for that purpose.
http://enfieldneurology.com/headache.htm
Everybody is different - lots of people take Lamictal and LOVE it. No side effects except the good ones, like for some people it evens out moods.
My worst side effects on Lamictal are brain fog and insomnia. The insomnia is big time insomnia, like 2-3 hours sleep a night insomnia. The brain fog makes life difficult when it gets really bad, but NOWHERE near as bad as I was on Topamax or Trileptal. On trileptal I'd just sit there and stare sometimes - not a seizure, just an empty brain. Not good. So for me Lamictal is very far from perfect but it's the best of the bunch. I have a bunch of good days when it comes to the brain fog thing. Not many good days with the headache thing.
There is a newly added package insert black box warnings for Lamictal and asceptic meningitis, but that is really rare, so no worries.
http://www.fda.gov/Drugs/DrugSafety...ormationforPatientsandProviders/ucm221847.htm