Title:Human Data on Pharmacokinetic Interactions of Cannabinoids: A Narrative
Review
Volume: 30
Issue: 4
Author(s): Cecilia Maldonado, Raquel Peyraube, Pietro Fagiolino, Florencia Oricchio, Leticia Cuñetti and Marta Vázquez*
Affiliation:
- Department of Pharmaceutical Sciences, Faculty of Chemistry, Universidad de la República, Montevideo, Uruguay
Keywords:
Cannabidiol, delta (9)-tetrahydrocannabinol, medicinal cannabis, pharmacokinetics, drug interactions, human data.
Abstract: Concomitant use of cannabinoids with other drugs may result in pharmacokinetic drug-drug interactions,
mainly due to the mechanism involving Phase I and Phase II enzymes and/or efflux transporters. Cannabinoids
are not only substrates but also inhibitors or inducers of some of these enzymes and/or transporters.
This narrative review aims to provide the available information reported in the literature regarding human data
on the pharmacokinetic interactions of cannabinoids with other medications. A search on Pubmed/Medline,
Google Scholar, and Cochrane Library was performed. Some studies were identified with Google search. Additional
articles of interest were obtained through cross-referencing of published literature. All original research
papers discussing interactions between cannabinoids, used for medical or recreational/adult-use purposes, and
other medications in humans were included. Thirty-two studies with medicinal or recreational/adult-use cannabis
were identified (seventeen case reports/series, thirteen clinical trials, and two retrospective analyses). In
three of these studies, a bidirectional pharmacokinetic drug-drug interaction was reported. In the rest of the
studies, cannabinoids were the perpetrators, as in most of them, concentrations of cannabinoids were not measured.
In light of the widespread use of prescribed and non-prescribed cannabinoids with other medications,
pharmacokinetic interactions are likely to occur. Physicians should be aware of these potential interactions and
closely monitor drug levels and/or responses. The existing literature regarding pharmacokinetic interactions is
limited, and for some drugs, studies have relatively small cohorts or are only case reports. Therefore, there is a
need for high-quality pharmacological studies on cannabinoid-drug interactions.
