Safety of Herbs and Vitamin Supplements

Cathy Wong: Many people believe that herbs are harmless and free of side effects. What are some of the problems we are seeing as a result of this belief that "natural is safe"?

Paul Saunders: Natural is not synonymous with safe. I vividly remember one patient calling me up, thinking that she was having a heart attack. It was a Saturday evening and I told her to go to the emergency department. I asked her if she had taken anything - it turned out that she had tried a diet product containing an herb called ephedra, which can cause heart palpitations if taken in high enough doses, especially on an empty stomach. She was also menopausal and having hot flashes, which only exacerbated the problem.

CW: St. John's Wort has also received a lot of media attention recently.

PS: Yes, there is some research concerning St. John's Wort and potential interactions with Indinavir, which is an HIV drug, digitalis, which is in a cardiac drug, and a variety of other drugs. So the consumer has to use some caution. Herbs and supplements are natural, but they are medicines in the traditional systems of medicine, like Chinese medicine, Ayurvedic medicine from India, and within the naturopathic community. Dosage makes all the difference between whether it's used properly or not and what side effects may appear. This is where the practitioner comes in. There are times when you need professional advice to help make decisions about what to do.

CW: With more people using natural products, are we seeing more adverse effects from drug interactions?

PS: We are starting to see drug interactions. We've seen some, for example, with gingko, which we think of as a relatively safe herb. There are two cases in the literature of gingko causing intraocular bleeds, which is bleeding inside the eye. One was an older gentleman in his seventies, and the other, surprisingly, was a young woman in her thirties with no prior history. We're going to see more interactions documented. Herbs interacting with medications are not as common as side effects from pharmaceutical drugs. That said, the outcomes can still be significant; the numbers do not negate the significance of the problem.

CW: Because of current regulatory standards, manufacturers often do not print safety warnings on the labels, perhaps so they don't scare off the public and reduce sales. By omitting this important information, however, it seems that they may be promoting the idea that natural products are harmless.

PS: That's true and unfortunately the Canadian government has some guilt to play, in that manufacturers are not required to print warnings, such as "do not take this herb if you are pregnant, menopausal, or using drug X". This has certainly been unfortunate because there should be warnings on labels but the governments have not required it. Labels should state "use only for self-limiting conditions" or "if you are not feeling better in a week or two, see a professional" or "do not take this if you are pregnant or menopausal". Getting back to our example with ephedra, there should also be a different dose for seniors and children. The regulations are not in place yet for a consistent label, but they are coming.

CW: One concern I have is that with respect to herbs and supplements, drug stores are selling an image of reliability and authenticity when, in fact, many of the herbs sold are from mainstream companies that may be known for their vitamins but do not necessarily apply the same quality control standards to herbs and supplements.

PS: It is big money so companies are getting into it, many of them overnight. Companies that have typically been involved with prescription drugs and vitamins are getting into herbs and supplements because they see it as a potential source of profit. But who are they hiring to do the job, and are they maintaining quality standards? This is something I think the consumer has to be cautious about. People go to the drugstore or grocery store and think, "I know this brand, I took their vitamins when I was a kid. The herbs must be great!" But are they? That's a big question; unless you visit the factories and see where they grow the herbs and observe their quality control practices, you do not really know. I had the opportunity to visit some of these factories; some of them are great, but some have areas to improve. We have to use caution. You might ask around and find out who has had success with the particular herb or supplement - your friendly pharmacy or grocery store may not always be your best source.