Amlodipine
"Just to update an older review:  Amlodipine has completely eliminated my migraines.  I haven't had a single migraine since I started taking 10mg of Amlodipine about 3.5 years ago.  I used to have 2-4 full blown 18 hour -2 day migraines a month.  No side effects or downside to medication so far.  It's worth a try."