Toxicity from bodybuilding supplements and recreational use of products containing 1,3-dimethylamylamine

To the Editor: 1,3-Dimethylamylamine (DMAA) is a substance with amphetamine-like effects found in bodybuilding and weight-loss products and recreational drugs (also marketed as methylhexaneamine, dimethylpentylamine and geranium).1 DMAA was recently banned in Australia and other countries owing to toxicity, lack of health benefits, and concerns about long-term safety and potential for misuse.2 However, published evidence for safety concerns has been remarkably limited; just a few cases report cerebral haemorrhage and cardiomyopathy.1

Many adverse effects from products containing DMAA have been reported by members of the public and health professionals to the NSW Poisons Information Centre (NSWPIC). We searched product and ingredient names obtained from a Human Performance Resource Center list3 by free-text searching on the NSWPIC database, as described previously, from 1 January 2004 to 12 October 2012.4 J A B performed the data extraction and coding, and N A B assisted where notes from telephone calls were unclear.

Over the last 3.5 years of the study period, 50 calls reported adverse effects in adults from recreational (16) or “therapeutic” (33) use of DMAA-containing products (many of which contain other ingredients, such as caffeine); intent of use was undetermined in one case. Calls increased over this time: five in 2009, four in 2010, 12 in 2011 and 29 in 2012. The median recorded age of adults exposed to DMAA was 20 years (range, 15–40; n = 17), and among those for whom sex was recorded there were more men (28) than women (17). In addition, five children aged 1–3 years accidentally ingested DMAA. A 2-year-old who ingested AmphetaLean required overnight hospitalisation and midazolam for agitation and tachycardia. The range of symptoms reported for adults is shown in the Box. Symptoms persisted for more than 12 hours in at least six people.

The number of calls reporting adverse effects from ingestion of products previously classified as “supplementary sports foods” is remarkable. PICs have the potential to provide toxicovigilance data, particularly for products that fall outside conventional medicine and chemical regulations and patterns of use.5 In just 3 years, our PIC alone accumulated more cases than the number used by the United States Food and Drug Administration to support action against DMAA.6 The NSWPIC only receives half of Australia’s PIC calls. Earlier signal detection through prospective follow-up of cases by an Australian network of PICs is feasible. Only further monitoring will determine whether problems from the illicit use of DMAA or other multi-ingredient sports supplements promoting “legal highs” have been solved by regulatory action.