Dr. Michael Smith, ND, associate dean of research at the Canadian College of Naturopathic Medicine, New York, Ont.

BALTIMORE—The oft-heard statement that herbal supplements are virtually free of adverse effects says as much about the absence of mandatory reporting as about the herbs themselves.

While the Food and Drug Administration does maintain a registry of adverse events associated with herbs, current laws do not require physicians or hospitals to report these occurrences, nor do they oblige FDA to actually follow-up reported incidents. This makes it difficult to interpret what little data is there.

“You need to know there is a problem before you can act intelligently,” said Dr. Michael Smith, a naturopathic physician and pharmacist, who is associate dean of research at the Canadian College of Naturopathic Medicine, New York, Ont. Speaking at a conference on applying scientific methods to ensure quality of natural products, Dr. Smith stressed the need for better surveillance.

This is not to imply that good quality medicinal herbs, when used properly, are particularly dangerous. In published clinical trials, there are few serious adverse effects seen with botanical medicines. “The reality is, adverse events that do occur are usually due to poor quality supplements. Garbage products will lead to bad outcomes,” said Dr. Smith.

But without ongoing national surveillance, only the most extreme and egregious cases come to light, often in a flurry of media hysteria, which obscures the overall picture. “It is clear we need a better system,” said John Cardellina, PhD, vice-president of botanical science and regulatory affairs of the Council for Responsible Nutrition, an industry group.

“The FDA’s system is the only general, centralized one. The problem is that there is no follow-up. They log reports verbatim from medical professionals and the public, however complete or incomplete, reasonable or unreasonable. FDA does not have the resources to investigate the reports,” he said in an interview.

Some supplement companies maintain their own databases of reported adverse effects related to their products. But this information is proprietary and not widely accessible.

North of our borders, the situation is not much better, said Dr. Smith. Health Canada, the Canadian national health care system, requests that physicians report suspected herbal side-effects and drug interactions through the same channels as for conventional pharmaceuticals. But there is no mandate to do so, and Dr. Smith expects that under-reporting is the rule in Canada, too.

In Europe, where herbal medicine is more integrated into general medical practice, surveillance tends to be tighter. Some of the European governments have mandatory reporting systems as part of their national health care systems. Beyond these, there are a number of voluntary international surveillance systems, which doctors worldwide can access online.

The European Pharmacovigilance Society, a multinational agency created in the 1970s after the thalidomide crisis, compiles annual data on side-effects from herbal medications across the continent. In 1997, EPS logged roughly 9,000 suspected herbal adverse events; approximately 6,000 were associated with use of single-ingredient herbal products.

In the UK, the University of Exeter hosts an independent, voluntary adverse events reporting system, part of the PhytoNET botanical information and education project. PhytoNET (www.exeter.ac.uk/phytonet) assembles a wealth of information on medicinal plants, efficacy and safety, regulatory updates, and the adverse drug reaction surveillance system. It is maintained by the European Scientific Cooperative on Phytotherapy (ESCOP), a cooperative established in 1989, and including organizations and university departments from 11 countries.

The relative lack of careful surveillance in the US. reflects several factors, said Dr. Smith. The fact that herbs are regulated as foods rather than drugs is one. But this is compounded by the historic lack of willingness within orthodox medicine to explore botanicals. The ideological wall, though crumbling, still intimidates patients.

“Clearly, two-thirds of complementary medicine users do not even tell their MDs that they are using these modalities. Doctors cannot report adverse events when they are not even aware of what their patients are using.”

On the patient side, many herb users simply assume that because the source plants are “natural,” they are de facto safe. “The perception of the spirituality and gentleness of herbs can lead people to entirely suspend their safety concerns,” he said.