Energy drinks: health risks and toxicity

Synthetic, caffeinated high-energy drinks are now common, and targeted at young people. The consumption of these drinks has increased significantly over the past 10 years – 2 in particular (Red Bull and ‘V’) account for over 97% of sales in this multimillion-dollar industry. As a result, there is an increase in the incidence of toxicity from caffeine overdose reported to hospitals and poison centres.

The main active ingredients of these drinks include varying amounts of caffeine, guarana extract, taurine and ginseng. Additional amino acids, vitamins and carbohydrates make up the remainder of the supposedly beneficial ingredients.

Adverse reactions and toxicity from high-energy drinks are mainly due to their caffeine content. In this study, the authors described the epidemiology and toxicity of caffeinated energy drink exposure in Australia. They used a retrospective observational study analysing data from calls regarding energy drink exposure recorded in the database of the Australian poisons information centre over 7 years to 2010.

Callers reported 297 exposures to energy drinks, which showed an increasing annual trend from 12 in 2004 to 65 in 2010. The median age of the 217 subjects with recreational exposure was 17 years and 57% were male. One hundred recreational users also ingested other substances, mainly alcohol (50) or other caffeinated products (44). The number of energy drinks consumed in one session varied greatly. Most subjects who reported recreational use reported symptoms (87%). The most common symptoms were palpitations, agitation, tremor and gastrointestinal upset. Twenty-one subjects had signs of serious cardiac or neurological toxicity, including hallucinations, seizures, arrhythmias or cardiac ischaemia. At least 128 subjects (57 with no co-ingestants) required hospitalisation.

The authors concluded that reports of caffeine toxicity from energy drink consumption are increasing, particularly among adolescents, warranting review and regulation of labelling and sale of these drinks.

Gunja N, Brown JA. Med J Aust 2012;196:46-49. doi:10.5694/mja11.10838