Sudden onset of headache, nausea, sweating, commonly caused by the following diseases: 1, digestive system diseases common, accompanied by headache, nausea, sweating, such as vomiting and bloating, diarrhea, constipation, usually triggered by acute gastroenteritis, which can be taken to protect the gastric mucosa drugs, while taking anti-inflammatory drugs, intravenous rehydration can be treated. 2, headache, nausea, sweating common causes and hypoglycemic reaction . When blood sugar is lower than 3.9mmol/L, nausea, sweating, palpitations, panic with headache will occur. In this case, intravenous 5% glucose injection can also relieve the symptoms.3. If acute cerebrovascular blood supply is inadequate, especially when the blood supply to the vertebrobasilar artery is insufficient, there will be headache with nausea and false sweating. At this time, oral medications to improve cerebral ischemia, such as Jinadu oral tablets, can be taken to observe the situation, and if the symptoms do not improve, it is necessary to go to the hospital immediately.