Taurine

Taurine, also known as 2-aminoethanesulfonic acid, is a biologically important chemical compound. Its empirical formula is C₂H₇NO₃S. It is not an essential nutrient in humans: It can be synthesized internally from cysteine and pyridoxine. Dogs can also synthesize the compound, but cats cannot.

There is a widespread misconception that taurine is an amino acid. Although it contains an amino group, it lacks the requisite carboxyl group.

In human metabolism it has two major roles. It is a neuroinhibitory transmitter and is part of the emulsifying bile acid chenodeoxychloic acid. It has been linked to a number of other metabolic functions but its use is not clear.

It has been tested medically in the treatment of congestive heart failure, cystic fibrosis, diabetes, epilepsy and several other conditions.

Taurine is one of the ingredients commonly found in 'energy drinks' (which often feature caffeine and/or other stimulant ingredients) such as the drink Red Bull.