Assessing Natural Product-Drug Interactions: An End-to-End Safety Framework

Regul Toxicol Pharmacol. 2016 Apr:76:1-6. doi: 10.1016/j.yrtph.2016.01.004. Epub 2016 Jan 9.

Abstract

The use of natural products (NPs), including herbal medicines and other dietary supplements, by North Americans continues to increase across all age groups. This population has access to conventional medications, with significant polypharmacy observed in older adults. Thus, the safety of the interactions between multi-ingredient NPs and drugs is a topic of paramount importance. Considerations such as history of safe use, literature data from animal toxicity and human clinical studies, and NP constituent characterization would provide guidance on whether to assess NP-drug interactions experimentally. The literature is replete with reports of various NP extracts and constituents as potent inhibitors of drug metabolizing enzymes, and transporters. However, without standard methods for NP characterization or in vitro testing, extrapolating these reports to clinically-relevant NP-drug interactions is difficult. This lack of a clear definition of risk precludes clinicians and consumers from making informed decisions about the safety of taking NPs with conventional medications. A framework is needed that describes an integrated robust approach for assessing NP-drug interactions; and, translation of the data into formulation alterations, dose adjustment, labelling, and/or post-marketing surveillance strategies. A session was held at the 41st Annual Summer Meeting of the Toxicology Forum in Colorado Springs, CO, to highlight the challenges and critical components that should be included in a framework approach.

Keywords: Cytochrome P450; Dietary supplements; Drug interactions; Herbal medicines; Metabolic enzymes; Natural products; Transporters.

Publication types

  • Congress

MeSH terms

  • Animals
  • Biological Assay
  • Biotransformation
  • Dietary Supplements / adverse effects*
  • Dietary Supplements / standards
  • Dose-Response Relationship, Drug
  • Drug-Related Side Effects and Adverse Reactions
  • Herb-Drug Interactions*
  • Humans
  • Pharmacovigilance
  • Plant Preparations / administration & dosage
  • Plant Preparations / adverse effects*
  • Plant Preparations / pharmacokinetics
  • Plant Preparations / standards
  • Polypharmacy
  • Quality Control
  • Risk Assessment
  • Toxicity Tests / methods*
  • Toxicity Tests / standards

Substances

  • Plant Preparations