Australian researchers this week called on government regulators to bolster oversight of herbal remedies due to concerns about potential health consequences and labeling inaccuracies.
The authors of a study in The Medical Journal of Australia wrote that although many herbal remedies are likely safe, their potential risks are poorly understood — particularly if they interact with prescription medications.
In addition, scientists warned that "light-touch regulation" could allow for inconsistent dosing, improper listing of ingredients or contamination by pharmaceuticals or toxins.
The analysis reviewed past literature regarding herbal remedies and health complications but said that most assessments rely on older studies due to a relative lack of recent investigations.
Researchers said that more analysis was needed, particularly because the use of herbal medications skyrocketed in Australia and the U.S. — and patients often fail to discuss their use with physicians.
"The lack of regulation and monitoring of traditional herbal preparations in Australia and other Western countries means that their contribution to illness and death is unknown," researchers wrote in the study.
Studies included in the review detailed a wide range of pharmaceuticals, pesticides and heavy metals detected in herbal products as well as plant species that were improperly substituted. The side effects of Aristolochia species, researchers noted, could include kidney failure.
The addition of toxic plant or animal substances could also lead to a variety of potentially deadly problems, and the study noted that some products were derived from "endangered animals such as the snow leopard."
The authors said that drug regulators — particularly Australia's Therapeutic Goods Administration — should increase their evaluations of herbal remedies and prosecute companies that misrepresent their products.
"How many more adverse drug reactions involving herbal products are needed before more attention is given to this important public health problem?" researchers asked.
TGA officials, however, responded that the study was "grossly misleading" regarding herbal medicines registered with the agency.
“The thrust of the MJA paper, that regulation of complementary medicines in Australia is inadequate, is contrary to the finding of the recent independent Expert Panel Review of Medicines and Medical Devices Regulation, which found that most submissions to the review were generally supportive of the current regulatory framework, but that there were opportunities to improve consumer confidence in the efficacy of listed medicines," TGA officials told the journal.