Red Bull and vodka has become somewhat of a staple drink for club-going young people in need of an energy fix as they party till the wee hours of the morning.
However, scientists are finding more evidence that these caffeine-charged alcoholic cocktails are hazardous to one's health.
Researchers found that while the combination cocktail of uppers and downers can reduce some of alcohol's sedating effects, they also found that mixing alcohol with energy drinks can lead to a range of serious health problems like heart palpitations, sleeping difficulties as well as jolt and crash episodes.
A new study, expected to be published in November in the journal Alcoholism: Clinical & Experimental Research, found that people who use energy drinks as a mixer for were about six times more likely to suffer heart palpitations compared to those who drank their alcohol straight or with a normal soft drink like soda or juice.
People who mix energy drinks with alcohol are also four times more likely to have trouble sleeping and were more likely to suffer tremors, irritability and so-called "jolt and crash episodes" or sudden, bouts of energy followed by long periods of exhaustion.
These symptoms are very similar to those produced by caffeine, one of the main ingredients in popular energy drinks like Red Bull and Monster Energy.
Red Bull contains 80mg of caffeine per 250 ml can compared to Monster Energy which contains nearly 85mg of caffeine per 250 ml, which is around the same the caffeine content in two cans of cola and a large cup of coffee.
"The reported side-effects of energy drink/alcohol consumption are similar to those reported by consumers of caffeine," said Andrea Carr of the University of Tasmania.
"To avoid these, consumers of energy drinks alone or combined with alcohol should be aware of the caffeine content of their drinks and any additional caffeine that they may have consumed that will contribute to an exacerbation of these effects," Carr added.
Past studies have suggested that because drunkenness is somewhat masked by energy drinks, the masking effect could lead to impaired judgment, leading people to do things they might do otherwise like drinking and driving or getting into fights.
Interestingly, the latest study, consisting of 403 men and women between the ages of 18 and 35, found that people who drank energy drinks were actually less likely to engage in risky behavior when drinking, possibly because they were less likely to experience the full-blown psychological and physiological sedation side-effects of alcohol like clumsiness, nausea, slurred speech, confusion, and exhaustion.
"However, they also had a greater chance in alcohol/energy drink sessions of experiencing several side-effects related to over-stimulation, including heart palpitations, increased speech speed, sleeping difficulties, agitation and tremors, jolt and crash episodes, and irritability and tension," co-author Amy Peacock of the University of Tasmania warned in a statement.
More research needs to be done on the physiological and psychological effects of energy drinks and alcohol, especially because sales of energy drinks have "increased exponentially in the last few years," Peacock said.
Other researchers have linked energy drinks with heart problems, saying that just one can of these caffeine-charged drinks can raise blood pressure and make blood more 'sticky', leading to an elevated risk of heart attacks and strokes.