Sale of kava extract in some health food stores
===============================================

* Edward Mills
* Rana Singh
* Cory Ross
* Edzard Ernst
* Joel G. Ray

## Abstract

IN JANUARY 2002, HEALTH CANADA ISSUED AN ADVISORY, followed by a ban in August 2002, on the sale of herbal kava. One month after the advisory, 22 (67%) of 33 health food stores approached were selling kava. Two months after the ban, 17 (57%) of 30 stores continued to sell kava. These findings demonstrate that health food stores may need to be better informed about the sale of restricted natural health products.

Some herbal products are used to treat mild psychiatric symptoms, including kava extract for anxiety.1 In January 2002, Health Canada issued a health advisory about the potential for fatal liver toxicity associated with kava use,2 followed by a ban on its sale issued in August 2002.3 We examined whether health food stores continued to recommend or sell kava following the federal health advisory and subsequent ban.

We identified all health food stores centrally located within a single large Canadian city, using the local business telephone directory and personal contacts. Thirty-four stores were identified as retail natural health product sales outlets.

In February 2002, 1 month after the federal advisory, 8 trained simulated customers (6 women and 2 men) were instructed to browse around the assigned health food store until approached by an employee. Each then declared that he or she was experiencing anxiety and asked the employee for a treatment recommendation. The simulated customer inquired about the possibility of interactions between the recommended treatment and other drugs. The customer was to disclose that he or she was taking a benzodiazepine only if asked about current medication use. Case reports indicate that kava may enhance the effects of benzodiazepine use.4 The simulated customer also inquired about the employee's training in complementary and alternative medicine.

In November 2002, more than 2 months after the federal ban, the 8 simulated customers revisited their respective health food stores to determine whether kava could still be purchased. They then asked employees if they knew about the product's safety record.

After the advisory stage of the study, a letter was sent to each health food store owner informing him or her about the study, and each was given the opportunity to request exclusion from the study. This study was conducted in accord with the Canadian *Tri-Council Policy Statement*5 and was approved by the Canadian College of Naturopathic Medicine Research Ethics Board.

One of the 34 stores contacted asked to be excluded. Among 33 store employees queried, 10 (30%) had received training in complementary and alternative medicine, of whom 7 (21%) had some formal education in complementary and alternative medicine at the community college or university level. Other sources of education included suppliers, books and in-store training.

In the 33 stores that were sampled following the federal advisory, 22 employees (67%) recommended kava for the treatment of anxiety. Eight of the 22 employees (36%) inquired about the customer's prescription drug use, 9 (41%) mentioned potential adverse effects of kava, and 5 (15%) discussed the potential for kava–drug interactions.

After the federal ban, 30 stores were included in the analysis; 3 stores had closed. Seventeen stores (57%) continued selling kava, placing it directly on the shelf (11 stores) or behind the counter (6 stores). Six (35%) of the 17 employees at stores that continued to sell kava said that they knew about the federal ban.

We used a participant-as-observer method to best simulate the real-life interaction between a customer and store employee,6 but could not be certain that every simulated customer interacted with, or perceived the advice of, each employee in a consistent manner. Our selection of a limited number of stores from within a single city might affect the applicability of these data to other Canadian centres. We also acknowledge that 1 or 2 months may have been insufficient time to allow health food stores to respond to the advisory or ban.

More than 35% of Canadians take nutrient supplements, and 15% use herbal products.7 Health food store employees are often the only source of information about health products, especially because many people do not inform their physician about herbal product use.8 However, in our study, most health food store employees did not have formal postsecondary training in complementary and alternative medicine.

Despite a federal health advisory and ban, many health food stores appeared to continue to sell kava in Canada. Natural health products share with prescription drugs the potential to cause harm.9 In our study, health food stores in a large Canadian city continued to sell a product that had been documented to cause harm. In the face of clear evidence supporting a change in policy toward the sale of kava, the product remained on the shelves of some health food stores.

𝛃 See related article page [1163](http://www.cmaj.ca/lookup/volpage/169/1163)

## Footnotes

*   This article has been peer reviewed.
    
    *Contributors:* Edward Mills conceived the study, performed the analysis and wrote the initial drafts. Rana Singh coordinated the participants. Cory Ross and Joel Ray co-conceived the study. Edzard Ernst assisted with methods issues. All authors contributed to drafting the article.
    
    *Acknowledgements:* We thank Cinzia Genuardi, Tanya Gokavi, Andrea Kenny, Laura Imola, Chad Sheehy, Tina Konstantinou, Stella Nonis, Danielle Rideout and Dileep Korah for their assistance in collecting the data for this study.
    
    *Competing interests:* None declared.

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