The causes of headache, weakness and nausea have many aspects, depending on the degree of headache, nausea, weakness, as well as the onset of the triggers and previous underlying diseases to be analyzed.1, if there is a history of migraine, neurological headache, a category of functional headache, this attack is not significantly different from the previous, to consider that it is caused by functional headache.2, if there is no previous history of headache, a sudden onset of severe headache, The symptoms of weakness and nausea should be considered to be caused by serious cerebrovascular diseases, such as cerebral hemorrhage, subarachnoid hemorrhage, encephalitis, meningitis, this kind of problem can not be excluded, and must consult the hospital in time to carry out the relevant examination to clarify the diagnosis.