The sale of Red Bull is prohibited in some countries, usually due to its taurine content or its alleged high level of caffeine. However, many countries which formerly banned Red Bull (and similar energy drinks) have revised their legislation to allow drinks containing taurine or higher amounts of caffeine, including Switzerland (1994) and Finland (2005). As of 2007, Red Bull remains prohibited as a soft drink in Norway, Uruguay, Denmark, and Iceland.

In 2001, the drink was investigated by the Swedish National Food Administration after being linked to the deaths of three consumers, and was completely cleared. It has been subject to a number of other health concerns regarding glucuronolactone, a precursor of taurine. Glucuronolactone is a naturally occurring chemical compound produced by the metabolism of glucose in the human liver. It has received some notoriety due to urban legends that it was a Vietnam War-era drug manufactured by the American government. The rumor goes on to say that it was banned due to several brain tumor-related deaths. The rumor has since been proven false, as neither the cited British Medical Journal article nor the "banning of its consumption" ever occurred. Due to the link with taurine, only energy drinks without taurine are sold in France, but infant formula sold there (and worldwide) is commonly supplemented with taurine. Furthermore, no warnings appear on the Food and Drug Administration website regarding its potential to cause brain tumors or other maladies

A common concern regarding the beverage is its supposedly high caffeine level. Proponents of the beverage counter critics by stating that a serving has roughly the same amount of caffeine as that found in a cup of coffee.

Studies have proven that there is a positive link between drinking Red Bull and reducing levels of cortisol, but it may also lead to a high blood-pressure problem if drunk to excess.

Pieces of advice regarding Red Bull
1) Results of a small study suggested to avoid the drink in case of suffering high blood pressure or heart disease
2) Swedish National Food Administration warned that Red Bull should not be consumed combined with alcohol or after strenuous exercise
3) Red Bull spokesperson recommended the consumption of no more than one to two cans. There are examples of people suffering heart disturbances after drinking eight cans of Red Bull.

Source: Wikipedia