A migraine is a type of severe and painful headaches. There are many reasons for a migraine. However, researchers do not have any definitive explanation but some of the main reason are a central nervous disorder, irregularities of blood vessel system or vascular system, and abnormalities and imbalance of brain chemicals or the pathway of nerves.

Though the main cause of a migraine is still unknown it is found that genetic and environmental factors are the major cause of a migraine. When there is a change in the brainstem and there is some imbalance in brain chemicals a migraine occurs.