Communication between oncology team members and their patients about supplement use during conventional therapy is important. Patients’ understanding of the risks and benefits of supplements are often rooted in nonscientific or quasi-scientific online literature, books, and supplement manufacturers’ brochures, and word-of-mouth communication with other patients and well-intentioned family members, coworkers, and friends.5

Patients can only make informed decisions about the risks and potential benefits of supplement use during cancer therapy if they are aware of the unknowns and the evidence for interactions between supplements and cancer therapies. Although most patients with cancer do not discuss their use of CAM products with their cancer care teams, most of those who report using supplements say they want specialized consultations to discuss CAM use during cancer treatment.5 However, clinicians are not always prepared to discuss these issues with their patients; for example, physicians have reported being uncomfortable discussing the issue.9

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No randomized, controlled clinical trials have addressed how best to discuss these issues with patients, but researchers have developed some guidelines using the weaker evidence.16 They recommend discussing patients’ use of alternative medicines, with respect to their cultural beliefs. Oncology nurses should ask questions about their use of CAM products, and provide balanced, evidence-based advice. The discussion should be documented, and any reports of using alternative medicines or supplements should be noted. Some researchers have recommended monitoring for potential adverse effects associated with alternative treatments during conventional treatment.16

The uncertainties and concerns about dietary supplements—both their efficacy and their possible negative interactions with conventional cancer therapies—should be openly and clearly, but respectfully and supportively, communicated to patients.

Bryant Furlow is a medical journalist based in Albuquerque, New Mexico. 


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