What happens when energy drinks are combined with alcohol?

This is an article from studies of brown university.

Energy drinks are also used as mixers with alcohol. This combination carries a number of potential dangers:

• Since energy drinks are stimulants and alcohol is a depressant, the combination of effects may be dangerous. The stimulant effects can mask how intoxicated you are and prevent you from realizing how much alcohol you have consumed. Fatigue is one of the ways the body normally tells someone that they've had enough to drink.
• The stimulant effect can give the person the impression they aren't impaired. No matter how alert you feel, your blood alcohol concentration (BAC) is the same as it would be without the energy drink. People will misperceive their ability to perform complex tasks like driving or crossing a busy road. Once the stimulant effect wears off, the depressant effects of the alcohol will remain and could cause vomiting in your sleep or respiratory depression.
• Research has found that people drink more and have higher BACs when they combine alcohol and caffeine.
• Both energy drinks and alcohol are very dehydrating (the caffeine in energy drinks is a diuretic). Dehydration can hinder your body's ability to metabolize alcohol and will increase the toxicity, and therefore the hangover, the next day.

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