Menace to society: Age-old herbal remedies don't guarantee safety

Popular herbal medicines that have been used for many years should not be considered safe as researchers highlight gaps in toxicity and carcinogenicity testing.

In a commentary piece, researchers from Baylor College of Medicine and Stony Brook University highlighted the need for more effective regulation of herbal medicine use in developed and developing countries to prevent similar dangers to public health.

One of the researchers, Dr Donald Marcus, pointed to studies that demonstrated the plant Aristolochia’s threat to human health.

Aristolochia is believed to cause aristolochic acid nephropathy (AAN), a condition that can lead to renal failure and cancers of the urinary track.

While the ingredient is now banned in many countries, its cancerous affects are still being felt. Researchers from Stony Brook University in collaboration with urologists in Taiwan had isolated the mutational signatures of upper urinary tract cancers caused by aristolochic acid.

In genetically susceptible people, consuming Aristolochia can lead to the formation of complexes between a compound in Aristolachia and DNA in renal tissues.

These complexes lead to mutations in the TP53 tumour suppressor gene, which in turn initiate the process toward kidney cancer.  Additional studies have also shown a link in the development of liver and bladder cancer.

Industry claims

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Concerns were highlighted about an industry that claimed herbs were gentle, safe, effective, and natural alternatives to pharmaceuticals. (© iStock.com)

Marcus, a professor emeritus of medicine and immunology at Baylor, and Dr Arthur Grollman, distinguished professor of pharmacological sciences at Stony Brook University, also highlighted a burgeoning industry that claimed herbs were gentle, safe, effective, and natural alternatives to pharmaceuticals.

According to the two professors, these claims went as far as to attribute herbs as possessing unique properties that were not found in drugs. These herbs were considered less toxic and more effective when used in combination, a characteristic of traditional Chinese medicine.

They pointed to the use of ephedra. Once approved in the United States to treat symptoms of mild bronchoconstriction, the herb was shown to cause elevated blood pressure, myocardial damage and strokes when it was marketed as a dietary supplement to promote weight loss.

Ephedra was frequently blended with herbs containing caffeine and used to enhance athletic performance in young, otherwise healthy people, and caused numerous adverse cardiovascular effects.

“The USA, the UK, and other Western countries have been in the grips of an herbal medicine renaissance, sparked initially by individuals and groups who promote “natural” healing, commercial interests in advertising and sales of herbal products,” the paper stated.

“They are then further influenced by the counterculture of the 1960s and broad dissatisfaction with contemporary healthcare systems.”

Regulatory action

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Scientific evidence supporting the efficacy of herbal remedies or their demonstrated hazards were being overlooked. (© iStock.com/mtr)

The team believed countries such as Germany, France, and much of Western Europe was less affected by this trend.

In the UK, an important legal change took place when the Ministry of Health chose to accept documented statements that a particular herb had been used for an extended period of time without adverse effects as proof of safety and efficacy. The researchers pointed out that Aristolochia, would’ve easily passed such a test.

In the EU, more than 1,300 traditional herbal medical products have been registered by the health regulatory authorities of the 28 EU member states.

The EU is now debating regulatory guidelines for herbal remedies, which would consider efficacy as well as quality and safety.

This legislative approach combines scientific evaluation with data collected from many years of herbal medicine use.

“Harmonizing the process for evaluating and authorising traditional herbal medicines among EU countries will be difficult and fraught with compromises,” they said.

“It will be even more difficult to extend this approach to parts of the world where the philosophies of TCM and Ayurveda prevail.”

Marcus and Grollman also disagreed with the World Health Organization's (WHO) endorsement of the use of traditional herbal remedies, compiled on the basis that traditional medicine is of proven quality.

They expressed disappointment about the lack of scientific evidence supporting the efficacy of herbal remedies or their demonstrated hazards, as in the case of Aristolochia.

The authors emphasised that their primary concern was ‘the prevention of toxicities associated with herbal medicine and not a categorical rejection of traditional healing practices.’

“Herbal remedies pose a global hazard,” they concluded. “We encourage the global health community to take actions that will evaluate both long- and short-term safety, as well as the efficacy of botanical products in widespread use.”

Source: EMBO Reports

Published online ahead of print, DOI: 10.15252/embr.201642375 

“Global hazards of herbal remedies: lessons from Aristolochia.”

Authors: Arthur Grollman and Donald Marcus