The symptoms of dry mouth and headache may be related to upper respiratory tract infection, abnormal blood pressure, sinusitis, frontal sinusitis, cerebrovascular diseases, gastrointestinal diseases, as follows: 1, upper respiratory tract infection: the symptoms of dry mouth and headache with runny nose, nasal congestion and sneezing may be related to upper respiratory tract infection; 2, abnormal blood pressure: if the blood pressure exceeds 150/100mmHg, headache may occur and dizziness; 3, sinusitis, frontal sinusitis: if there is pain in the forehead or in the middle of the eyebrows, accompanied by symptoms such as dry nose, it may be related to sinusitis and frontal sinusitis; 4, cerebrovascular diseases: such as cerebral thrombosis, cerebral infarction, insufficient blood supply to the brain, cerebral ischemia, hypoxia, etc., may lead to symptoms of headache; 5, gastrointestinal diseases: if there are symptoms of headache, dizziness, stomach pain, diarrhea, it may be related to Gastrointestinal flu or gastroenteritis is related, if the diarrhea is strong dehydration will lead to dry mouth, you should go to the hospital for examination to determine the cause of the disease and then treat the symptoms.