My 3 year old grabbed my monster energy drink when i was in the other room and he drank the last half of it… the following is the result. Drinking too many energy drinks at one time or at a young age can cause caffeine intoxicity. The symptoms of caffeine intoxication are not unlike overdoses of other stimulants. It may include restlessness, fidgetiness, nervousness, excitement, euphoria, insomnia, flushing of the face, increased urination, gastrointestinal disturbance, muscle twitching, a rambling flow of thought and speech, irritability, irregular or rapid heart beat, and psychomotor agitation.[42] In cases of much larger overdoses, mania, depression, lapses in judgment, disorientation, disinhibition, delusions, hallucinations, and psychosis may occur, and rhabdomyolysis (breakdown of skeletal muscle tissue) can be provoked.[46][47] Extreme overdose can result in death Technically you can suffer from water intoxicity too.