Most people can identify the typical symptoms of a migraine: severe pain on one side of the head, sensitivity to light and sound, and nausea. The usual migraine symptoms differ from those of a typical stroke, which often causes confusion, difficulty moving and/or slurred speech. However, there is a rare form of migraine that can mimic a stroke: a hemiplegic migraine. According to the Indian Academy of Neurology, it often takes multiple episodes to diagnose a hemiplegic migraine.
Hemiplegia
A hemiplegic migraine often causes a condition called hemiplegia, in which one side of the body is either difficult to move (from muscle weakness) or will not move at all. According to the Indian Academy of Neurology, in some cases this lack of movement lasts longer than the headache pain, making a hemiplegic migraine difficult to distinguish from a stroke. When a person has a stroke, it often causes hemiplegia on one side of their body. Like a hemiplegic migraine, this condition may be temporary, especially in the case of a very mild stroke. In severe strokes, however, the condition persists and may become permanent.
Severe Headache
Severe head pain is not exclusive to a hemiplegic migraine, and may occur with almost any type of chronic headache. However, if a person has a sudden onset of a migraine with severe head pain, it can mimic the same type of head pain experienced by many stroke victims. In a hemiplegic migraine, according to the National Migraine Association, head pain often begins before the one-sided weakness. The same is often true for stroke, making the two difficult to distinguish.
Altered Mental Status
In some cases of hemiplegic migraine, the person may have a change in their cognition, or an altered mental status. This can range anywhere from mild confusion and disorientation to a coma-like state. Like hemiplegia, this typically resolves once the migraine is over. However, if a person has a stroke, a change in their mental status may last longer, or may persist indefinitely. Differentiating between the two can be a challenge, especially if the migraine comes on suddenly.
Ataxia
Ataxia is another word for uncontrolled or uncoordinated movement. When a person has a hemiplegic migraine, they may have difficulty coordinating their arms and legs, causing their movements to appear jerky or awkward. They may over- or under-shoot items they are reaching for, or have difficulty signing their name. This is a common stroke symptom. Like most other hemiplegic migraine symptoms, ataxia should resolve after the migraine attack is over. In a stroke, however, it often persists.
Visual Disturbances
Visual disturbances such as auras or a partially blocked field of vision can occur in many types of migraine, not just hemiplegic migraines. When a person having a migraine experiences an aura, they may see flashing lights or halos around objects. When someone has a stroke, they may experience double vision as well as auras, or they may have a portion of their vision blocked completely. In most cases of migraine, this symptom disappears after the attack. If a person is having a migraine that mimics a stroke, it may be difficult to distinguish the two without performing a multitude of diagnostic tests.
