Natural health product-drug interaction tool: A scoping review.

Abstract

Natural health products (NHPs), such as herbal medicines, probiotics, vitamins and minerals, are used regularly by 73% of Canadians.1 Many consumers believe that NHPs derived from plants (such as herbal medicines) are safe because they are “natural.”1 However, some plant-derived NHPs can interact with pharmaceutical medications, potentially resulting in serious harm for patients.2 A recent active surveillance study found that approximately 45% of consumers presenting to a Canadian pharmacy report using NHPs and prescription drugs concomitantly, with 7.4% describing an adverse event.3 It is important for clinicians to initiate patient communication about NHP use and be knowledgeable about the potential risks to ensure patient safety. Unless clinicians ask, they may be unaware of patient NHP use. Most NHPs can be purchased from many sources without involvement of a health professional, and many patients do not disclose NHP use to clinicians.4 However, education about NHP interactions is not always included within medical and pharmacy curricula,5 and new evidence on NHP–drug interactions is constantly emerging. In addition, a quick search of the medical literature might identify contradictory information or poor-quality reports that are challenging to interpret. Clinicians could benefit from effective knowledge translation tools to identify and prevent potential NHP–drug interactions in their patients. As pharmacists have confirmed the utility of a NHP–drug interaction grid6 as an effective knowledge translation tool,7 we undertook a scoping review to identify and incorporate new NHP–drug interactions.