Presence of Banned Drugs in Dietary Supplements Following FDA Recalls

The US Food and Drug Administration (FDA) initiates class I drug recalls when products have the reasonable possibility of causing serious adverse health consequences or death.¹ Recently, the FDA has used class I drug recalls in an effort to remove dietary supplements adulterated with pharmaceutical ingredients from US markets. Approximately half of all FDA class I drug recalls since 2004 have involved dietary supplements adulterated with banned pharmaceutical ingredients.^2,3

Prior research has found that even after FDA recalls, dietary supplements remain available on store shelves.⁴ However, it is not known if the supplements on sale after FDA recalls are free of the adulterants. In the present study, dietary supplements purchased at least 6 months after FDA recalls were analyzed to determine if banned drugs were still present.

Dietary supplements were analyzed if they met the following inclusion criteria: (1) recalled due to adulteration with pharmaceutical ingredients between January 1, 2009, and December 31, 2012^3,5; (2) available for purchase in July or August 2013 directly from websites of supplement manufacturers or retailers (as opposed to general e-commerce sites such as Amazon.com, eBay Inc, or Alibaba Group); and (3) the supplement name, manufacturer, and distributor listed on the purchased supplement was identical to the information provided in the FDA recall.

Dietary supplements were analyzed by Flora Research Laboratories (J.N-K.). Samples were labeled with the marketing claim on the supplement label (eg, weight loss, sexual enhancement, or sports enhancement), but did not include the supplement name, manufacturer, and prior FDA findings.

Analyses were performed using the same methods that the FDA’s field laboratories use to screen for clandestine adulteration. In short, dietary supplements were analyzed using either gas chromatography mass spectrometry or liquid chromatography tandem mass spectrometry in data-triggered mode. Adulterants, except for anabolic steroids, were confirmed against a standard using retention time, mass spectrum, and UV spectrum.

The FDA recalled 274 dietary supplements between January 1, 2009, and December 31, 2012. Twenty-seven of the 274 recalled supplements (9.9%) met our inclusion criteria and were analyzed. Supplements were purchased a mean (SD) of 34.3 (11.5) months after the FDA recall (range, 8-52 months). Seventy-four percent of supplements (20/27) were produced by US manufacturers.

One or more pharmaceutical adulterant was identified in 66.7% of recalled supplements still available for purchase (18/27; Table). Supplements remained adulterated in 85% (11/13) of those for sports enhancement, 67% (6/9) for weight loss, and 20% (1/5) for sexual enhancement. Of the subset of supplements produced by US manufacturers, 65% (13/20) remained adulterated with banned ingredients.

Sixty-three percent of analyzed supplements (17/27) contained the same adulterant identified by the FDA. Six of the 27 (22.2%) supplements contained 1 or more additional banned ingredients not identified by the FDA (Table). Some supplements contained both the previously identified adulterant as well as additional pharmaceutical ingredients. Banned substances identified in recalled supplements included sibutramine, sibutramine analogs, sildenafil, fluoxetine, phenolphthalein, aromatase inhibitor, and various anabolic steroids. One novel adulterant, benzyl sibutramine, was first described as recently as 2013.⁶

To our knowledge, this is the first study to determine if adulterants remain in supplements sold after FDA recalls. We found that 66.7% of recalled supplements still available for purchase at least 6 months after FDA recalls remained adulterated with banned ingredients.

Our study has several limitations. First, we limited testing to common adulterants expected based on marketing claims (eg, weight loss supplements were tested for adulterants commonly found in weight loss products). Second, our analyses may have failed to detect recently introduced drug analogs. Third, although every effort was made to purchase recently manufactured supplements, it is not known if all supplements were manufactured after the FDA recall.

Action by the FDA has not been completely effective in eliminating all potentially dangerous adulterated supplements from the US marketplace. More aggressive enforcement of the law, changes to the law to increase the FDA’s enforcement powers, or both will be required if sales of these products are to be prevented in the future.

Corresponding Author: Pieter Cohen, MD, 236 Highland Ave, Somerville, MA 02143 (pcohen@challiance.org).

Author Contributions: Dr Cohen had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Study concept and design: Cohen.

Acquisition, analysis, or interpretation of data: All authors.

Drafting of the manuscript: Cohen.

Critical revision of the manuscript for important intellectual content: All authors.

Statistical analysis: Maller, DeSouza.

Obtained funding: Cohen.

Administrative, technical, or material support: Maller, Neal-Kababick.

Study supervision: Cohen.

Conflict of Interest Disclosures: The authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Mr Maller reported receiving personal fees from NY State Senator Jeffrey Klein and SSP Nutrition outside of the submitted work. Mr Neal-Kababick reported being the vice chair of the US Pharmacopeia expert panel on Adulteration of Dietary Supplements with Drugs and Drug Analogues; reported being a co-owner of Flora Research Laboratories (some of the clients are dietary supplement manufacturers); and reported serving as an expert witness in cases involving the investigation of quality issues in the production of dietary supplements. No other disclosures were reported.

Funding/Support: This research was supported in part by a grant from Consumers Union.

Role of the Funder/Sponsor: Consumers Union had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Additional Contributions: We acknowledge Mercy Imahiyerobo, MPH, JD (Harvard School of Public Health), for her assistance in identifying recalled supplements; she was not compensated for her contribution. Ms Imahiyerobo is now with a private law firm.

Correction: This article was corrected on November 4, 2014, to fix the name of the study funder.