Migraine and cerebral hypoxia: a hypothesis with pharmacotherapeutic implications.

It is postulated that a migraine attack is a specific reaction pattern to an episode of focal cerebral hypoxia. This hypothesis holds that any type of focal brain hypoxia (and thus not only a vasospasm) may provoke a migraine attack. Indeed, as hypoxia is a result of an imbalance between energy supply and energy use, the former can be decreased and/or the latter be increased. Spreading cortical depression, leading to the aura, is believed to be another consequence of brain hypoxia occurring in classical migraine. There are no other genuine differences between classical and common migraine, according to the cerebral hypoxia theory. The latter theory may improve our understanding of the mode of action of antimigraine drugs. Certain calcium entry blockers have a direct protective effect on brain hypoxia, but some other pharmacotherapeutic approaches may also prevent cerebral hypoxia via an effect on brain metabolism, vasomotion or platelet behavior.