Yes, you can get pupils dilate because of a migraine. Migraine is a chronic disorder characterized with a moderate to severe headache due to the constriction and expansion of blood vessels in the brain. Ophthalmoplegic migraine can cause abnormal paralysis of the motor nerves of the eye and dilated pupils.
Generally speaking, it is possible for migraine to cause dilated pupil. Migraine is commonly associated with headaches, described as an intense pain of one temple. There are plenty of nerves and vessels in our brain, which is very complicated combination. Some study on migraine said the dilated pupil is caused by Postganglionic sympathetic nerve spasms during migraine. But the dilated pupil is only a temporary symptom, which can disappear without treatment. Actually we know that dilated pupil is related to nervous system. Once nervous system is sitmulated, it is easy to get pupil dilation. Other than migraine, the very common reasons for dilated pupil include drugs, some medications, dark light, fears, excitement, coffee, hormones and so on. Triggers to migraines also include hormones, coffaine, alcohol and so on. Hence you can understand the underlying between them. Hope this could be helpful.
Well, yes, when you have migraine, it is possible to have dilated pupils. As we know that when you suffer migraine, it will just increase your blood pressure, and then leading to high eye pressure. In that way, it can affect your eyes, leading to dilated pupils. So it is the common sign of migraine. Also, you should know that according to some experts, high blood pressure and drugs use, especially some emotion, such as anxiety can lead to dilated pupils. Anyway, to treat your migraine, the first job you should do is to heal your migraine.