Even though caffeine does not cause dehydration, drinking too much can cause the same symptoms. The most common is a headache, which can be avoided by drinking a lot of water.
Drinking too much caffeine does have some side effects. As a stimulant it could cause insomnia if consumed later in the day. Caffeine can lead to attacks of anxiety and irritability that often lead to a crash after it has been excreted from the body.Learn more about Nutritional Amounts & Limits