偏头痛主要由于脑动脉扩张,引起血管膨胀和搏动幅度增大,再牵涉到痛觉敏感的神经纤维而发生。过去,许多药物用于减轻偏头痛发作时的症状,其中主要有麦角胺(Ergotamine),常与咖啡因合用(麦咖片)治疗偏头痛。麦角胺具有特殊的收缩血 Migraine mainly due to cerebral artery dilatation, causing blood vessels to expand and increase the amplitude of pulsation, and then involve the pain sensation of nerve fibers and the occurrence. In the past, many drugs have been used to alleviate the symptoms of migraine attacks, including ergotamine, commonly used in combination with caffeine (megranium) for migraine. Ergotamine has a special contraction of blood