A new study published in JAMA Network Open
on Friday raises questions about the US Food and Drug Administration’s (FDA) oversight of adulterated dietary supplements.
The study, which analyzed data from FDA’s Tainted Products Marketed as Dietary Supplements database, found more than 776 instances of supplements containing hidden pharmaceutical ingredients from 2007-2016.
However, only 360 of the 776 adulterated supplements were subject to a voluntary recall, while 342 of the products were subject to a public notification by FDA. The remaining products were identified in either a news release, consumer update, warning letter to the manufacturer or in a single case, a Department of Justice press release.
Roughly a fifth of the tainted products were found to contain two or more hidden ingredients. In a handful of cases the authors found supplements that were subject to a voluntary recall or other FDA action over a hidden ingredient that were later found to have a different hidden ingredient.
“This indicates that these products continue to be sold and are potentially dangerous even after FDA warnings. This is alarming, especially considering that the FDA is only able to test a portion of products available on the market,” the authors write.
Unsurprisingly, the vast majority of the adulterated supplements were marketed for sexual enhancement (45.5%), weight loss (40.9%) or muscle building (11.9%) and contained ingredients such as sildenafil, the active ingredient in Pfizer’s Viagra, and sibutramine, an appetite suppressant that was withdrawn from the US market in 2010
due to safety concerns.
“These products have the potential to cause severe adverse health effects owing to accidental misuse, overuse, or interaction with other medications, underlying health conditions, or other drugs within the same dietary supplement,” the authors write.
Unlike pharmaceuticals and biologics, dietary supplements are not subject to premarket review and are classified as food under the 1994 Dietary Supplement Health and Education Act
. Supplements are also subject to labeling and good manufacturing practice (GMP) requirements and supplement makers are required to report certain adverse events to FDA.
FDA’s efforts to detect adulterated supplements include reviewing adverse event reports, screening international shipments and inspecting supplement makers.
In an accompanying commentary, Pieter Cohen, associate professor of medicine at Harvard Medical School, equates FDA’s handling of adulterated supplements to a dereliction of duty, arguing that the agency has more powerful tools in its arsenal, such as mandatory recalls, warning letters and product seizures, which it rarely uses against supplement makers.
Cohen also suggests that Congress could enhance FDA’s ability to regulate supplements by requiring companies to register their products with the agency before marketing them and granting FDA the authority to pull their registration if the products are found to contain hidden ingredients.