MONTREAL (PasseportSanté.net) June 9, 2005 – Inaccurate and biased information is circulating about interactions between natural health products (NHPs) and drugs, both within the scientific community and among consumers. In North America, in particular, researchers publish unnecessarily alarmist data that the headlines of the newspapers reproduce without any nuance. At least that is what several speakers passionately affirmed during a conference entitled “New rules of the game – Natural health products”, which was held this week in Montreal.1.
Bad science
Can soy phytoestrogens interact with replacement hormones and are they dangerous with a history of hormone-dependent cancer? Yes, according to several authors. No, according to pharmacist Jean-Yves Dionne, one of the speakers. “If phytoestrogens were estrogens, women who eat soy products would be sterile and there would be no Asian continent! »He launched to illustrate the lack of knowledge of NHPs in the scientific community.
“The most powerful phytoestrogen, genistein, has a thousand times weaker affinity for estrogen receptors than that of estradiol and cannot in any way affect the effect of a synthetic hormone. And, he continued, when it comes to hormone-dependent cancers, there is only one in vitro study. It indicates that pure genistein, in massive doses, stimulates two strains of breast cancer and inhibits two others. We cannot extrapolate from such thin data. Especially since epidemiological studies on dietary soybean consumption point to a preventive effect against cancer. ”
This is just one of the examples mentioned by Mr. Dionne who deplores the lack of knowledge and openness of the medical community. “A majority of patients, especially those with chronic illnesses, take both drugs and natural health products, but they don’t dare talk to their doctor for fear, and rightly so, of being ridiculed. ”
The brochure of the College of Physicians of Quebec
And yet, the College of Physicians of Quebec (CMQ) wants patients to talk about their consumption of NHP with their doctor. “We don’t want to promote or condemn the use of NHPs. However, as patients take it, we want to educate the public, doctors and pharmacists about possible interactions with drugs, ”D explained.r Francois Goulet2, spokesperson for the CMQ on the occasion of this conference.
In October 2004, the CMQ published, in collaboration with the Ordre des pharmaciens du Québec, two guides on interactions between NHPs and drugs. The one intended for the public is called “Natural Health Products – Talk to Your Doctor or Pharmacist”3 and the one intended for professionals, “Natural health products – To better advise your patients”4.
These guides have attracted negative comments from the NHP industry for an unnecessarily alarmist approach and a lack of knowledge in the field. “In the leaflet intended for the public, it is suggested that the risks of adverse effects from NHPs are the same as those of drugs, which is quite exaggerated,” said André Gagnon, president of Santé Naturelle. – Adrien Gagnon. In addition, it is recommended that NHPs be used for the short term, less than three months. However, in the case of glucosamine, the Natural Health Products Directorate (NHPD) of Health Canada specifies in its monograph that it must be used for at least two months before the beneficial effects start to appear. How can the consumer navigate it? », Lamented Mr. Gagnon.
Pierre Haddad, professor and researcher in the Department of Pharmacology at the University of Montreal, is also critical of the guide for professionals. “It presents in the same column the interactions demonstrated and the interactions suspected, which contributes to fuel the confusion that already reigns in this area,” he explained.
“Imperfect as they are, these guides are a first step,” insisted Dr.r Goulet. Their preparation and publication sparked a big debate within the CMQ: the most conservative members criticized us for promoting the use of NHPs, and the more open found the initiative rather positive. During preparation and at the time of consultations, some organizations criticized us for talking only about interactions between NHPs and drugs and not about the effectiveness of NHPs. We had to start somewhere and we chose a middle position ”.
Option Consommateurs: an inconsistent guide?
Another organization released a guide on interactions between NHPs and drugs. Option Consommateurs, an association dedicated to the defense and promotion of consumer interests, published in July 2004 an information brochure entitled “Natural health products and drugs: a sometimes risky mix”. “This document, printed in 255,000 copies5, contains data that do not agree with those in monographs prepared by the NHPD6 », Lamented Mr. Gagnon.
In fact, the interactions associated with black cohosh, for example, are not the same: the Consumer Option brochure mentions a decrease in iron absorption and an increase in the effect of hypertensive drugs, while nothing like this is stated in the Health Canada monograph7. “How do you want the consumer to find their way there? Option Consommateurs presents itself as the authority, while it is the NHPD that should play this role, said Mr. Gagnon. And these inconsistencies are all the more disturbing since this brochure was funded by Health Canada, which also oversees the NHPD … ”
Me Jannick Desforges, interim director of Option Consommateurs, specified that this guide was in fact being revised and that the NHPD was participating in this process. “How come this basic check wasn’t done before publication?” exploded Mr. Gagnon. The intention to inform consumers is not bad, but the dissemination of speculative data is not doing them a favor at all! “Me Desforges specified that it did not work directly on this file and therefore could not answer this question.
The NHPD
Mr. Gagnon also did not spare the NHPD which, according to him, is not always rigorous enough, despite its position of authority in the matter. “In the case of glucosamine, for example, the NHPD mentioned diabetes as a contraindication, which would have forced us to indicate it on our product. However, this information is inaccurate, even if it is taken up by several sources. It took us a year of dealing with the NHPD to make our point and the monograph will be amended, ”he said.
This is a point on which pharmacist Jean-Yves Dionne fully agrees: “Glucosamine does not affect diabetes. Tests on animals simulating insulin resistance have used a massive dose in the form of a continuous infusion, corresponding to 65 g per day in humans: we are very, very far from the usual dosages. In addition, an unlimited oral dose of glucosamine, integrated into the animal feed did not have an effect, ”he explained.8.
More consistency please
In such a context, how can we instill more coherence in this dossier? M. Dionne proposes the adoption of a classification similar to that put in place by Facts and Comparisons9, the bible of drug interactions for healthcare professionals in North America. “This ranking establishes a gradation of three aspects of interactions: severity, degree of documentation and probability. By giving these details, we would really shed light on the debate and we would have a valid reference tool, ”he says.
“It’s worth alerting when you have a significant, documented, credible risk. Some interactions are potentially serious, like that of ginkgo and warfarin (an anticoagulant), others are documented and serious, like that of St. John’s Wort which decreases the effect of indinavir, a medicine for AIDS patients. Let’s say it, but let’s be clear and don’t give the same importance to speculations based on in vitro data or a lack of knowledge of the mode of action of plants. We can protect consumers in a smart way. Is it by disseminating speculative information to the public? I have doubts. Is it by better training our professionals? I believe so, ”he concluded.
Several speakers, including Dr Goulet of the College of Physicians, have in fact underlined in broad strokes that the training of physicians and pharmacists is deficient, if not non-existent, in the area of NHP. This ignorance, often associated with negative prejudices, prevents them from adequately counseling their patients, who are however more and more numerous to take NHPs. “We want the attitudes and behaviors of physicians to change when it comes to NHPs,” said Dr Goulet. We have taken a first step with our guide and we intend to continue in this direction, but it is a long term job. ”
Françoise Ruby – PasseportSanté.net
1. This colloquium, organized by Insight, took place in Montreal on June 6 and 7, 2005 and brought together Quebec speakers from several sectors: the NHP industry, medicine and pharmacy, researchers, and consumer protection. Insight organizes business conferences on economic, legal and regulatory topics.
2. Dr Goulet is Deputy Director of the Practice Improvement Department of the Collège des médecins du Québec.
3. Document accessible at: www.cmq.org
4. Document accessible at: www.cmq.org
5. This document is available free of charge at Familiprix pharmacies, as well as at Uniprix pharmacies (Natural health products and drugs – Knowing the risks associated with their combined use). It is also accessible at the following address: www.option-consommateurs.org
6. The Natural Health Products Directorate monographs are available at: www.hc-sc.gc.ca
7. Black Cohosh Monograph, Natural Health Products Directorate, Health Canada: www.hc-sc.gc.ca
8. For more information on this point, consult our sheet on Glucosamine
9. Facts and Comparisons website address: www.factsandcomparisons.com
