Many energy drinks contain large amounts of caffeine which increases energy temporarily.
Energy drinks also contain a high percentage of sugar and other substances that allow only short-term influx of energy, but they are associated with certain dysfunctions in the body.
Energy drinks that contain sugar contribute to weight gain and intake of too much caffeine can lead to: high blood pressure, anxiety, insomnia, fast heartbeat.
The combination of energy drinks and alcohol is even more problematic. In fact the parallel consumption of energy drinks and alcohol can slow down sense of intoxication (drunkenness achievement time is prolonged) that can lead to greater intake of alcohol, and then you will have some serious problems because of excessive alcohol consumption.
Occasional consumption of energy drinks is fine. But if you constantly feel tired and want to have more energy choose healthier ways to boost your energy.
First you should do is to eat healthy food, sleep enough, and also to have some physical activity.