Symptoms of drinking too much coffee include indigestion, mental hyperactivity and poisoning. 1. Indigestion: Coffee contains caffeine, which excites the nerves. Excessive coffee consumption is prone to indigestion, such as nausea and vomiting, reflux, heartburn, and so on. 2. Mental exuberance: excessive consumption of coffee is also likely to cause mental exuberance, especially in the large amount of coffee before going to bed, but also affect normal sleep, sleep disorders, and in serious cases, even mental irritability and other symptoms. 3. Poisoning: Drinking too much coffee may also cause coffee poisoning, clinical symptoms can be manifested as dizziness, headache, thirst, dehydration, irritability, vomiting blood and so on. Drinking coffee in moderation generally does not appear adverse reactions, but also helps to refresh, but it is not recommended to drink too much coffee, so as to avoid coffee poisoning. If you feel unwell, it is recommended that you consult a hospital in time to avoid delaying treatment.