The FDA has issued warning lettersto 10 marketers of 1,3-dimethylamylamine (DMAA)-containing dietary supplements. FDA states that these products are adulterated due to allegations that the companies have not complied with certain provisions of the Dietary Supplement Health and Education Act (DSHEA).  

 In its warning letters, FDA excludes synthetically produced DMAA as a botanical constituent, as that term is used in DSHEA, and states that synthetic DMAA cannot be a dietary ingredient for use in a dietary supplement.
 
“As we have previously stated, AHPA disagrees with FDA’s view that human-synthesized constituents of botanicals are not dietary ingredients lawful for use in supplement products,” said Michael McGuffin, president of the American Herbal Product Association (AHPA). “The agency’s position on this ignores the fact that synthesized vitamins, minerals, amino acids, and botanical constituents were already marketed at the time DSHEA was passed. In AHPA’s view, if DMAA exists in geranium through the plant’s own synthesis processes, human-synthesized DMAA is also a lawful dietary ingredient.”
 
In the April 24 warning letters, FDA also states that there is no information demonstrating that DMAA is found naturally in the food supply. In a statement issued last September, Cantox Health Sciences International asserted that two analytical laboratories have demonstrated the occurrence of DMAA in the geranium plant, Pelargonium graveolens, which would corroborate data originally published in 1996.  
 
“AHPA looks forward to publication of this new analytical work,” McGuffin said.
 
The FDA warning letters also state without citation that the ingredient “narrows the blood vessels and arteries, which increases cardiovascular resistance and frequently leads to elevated blood pressure. This rise in blood pressure may increase the work of the heart such that it could precipitate a cardiovascular event, which could range from shortness of breath to tightening of the chest and/or a possible myocardial infarction (heart attack).”
 
Recently published studies on the effect of DMAA on healthy volunteers reported that the ingredient was generally well tolerated by participants.