Migraine: the platelet hypothesis after 10 years.

The proposal that migraine is a blood disorder and caused by a primary abnormality of platelet behaviour was first put forward in 1978. This paper outlines the basis on which the proposal was made and the way in which the platelet hypothesis can account for the many facets of the disorder. It also reports further studies of platelet composition and function which have been undertaken by a large number of independent workers during the past ten years. The results of their investigations provide strong additional support for the platelet hypothesis in migraine.