Vomiting after fever is usually not a good thing, considering that it may be caused by gastrointestinal colds, acute gastroenteritis, encephalitis and other diseases. 1. Gastrointestinal colds: gastrointestinal colds are mostly caused by viral infections, and patients will experience symptoms such as vomiting, fever, headache, and loss of appetite. If you don’t seek medical attention in time, complications such as viral myocarditis and shock may occur, so vomiting after a fever is not a good thing. 2. Acute gastroenteritis: upper respiratory tract infections are caused by viral, bacterial and other pathogen infections, and patients mainly manifest fever, nausea and vomiting, diarrhea and so on. Acute gastroenteritis can lead to a large loss of water in the patient’s body, which can cause shock, therefore, it is not good to vomit after fever. 3. Encephalitis: Encephalitis is caused by viral and bacterial infections and other pathogens, patients will have fever, convulsions, vomiting, headache and other symptoms. Encephalitis is a serious disease and can be life-threatening, so it is not a good thing to have this condition. Patients with fever and vomiting symptoms are recommended to go to the hospital in a timely manner, complete the relevant examinations, and follow the doctor’s instructions to avoid delaying the condition.