Feverfew Tincture for Migrane ok with standard BP medicines?? Anyone have a favorite?

Ihave been looking online and found some tinctures for migrane headache, containing feverfew, and some more of the 'traditional' headache herbs. Anyone use any particular tinctures with good resultes, or just feverfew tea?
Just making sure its safe for people on standard BP medicins, if anyone might know.

http://www.darcyfromtheforest.com/servlet/Detail?no=421