The ingredient inside coffee is mainly caffeine, which has a stimulating effect on the central nervous system. However, if a large amount of coffee is taken, it can easily lead to the manifestation of poisoning. Coffee poisoning: First, the symptoms of the central nervous system, such as dizziness, headache, nausea, vomiting, abnormal mental excitement, and even irritability and impaired consciousness. Second, it can affect the circulatory system, especially the function of the heart, which may lead to rapid heartbeat and even arrhythmia, and in serious cases, it may lead to cardiac arrest. Third, the side effects on the gastrointestinal tract, such as abdominal pain, nausea, vomiting, diarrhea and other manifestations.