Evidence of Potential Drug Interactions Between Cannabidiol and Other Drugs: A Scoping Review to Guide Pharmaceutical Care.

Abstract

Cannabidiol (CBD), a non-psychoactive cannabinoid with therapeutic potential, is increasingly used in combination with other drugs, raising concerns about potential interactions and their impact on safety and efficacy. This scoping review aimed to map the current evidence on CBD interactions across different drug classes and assess their clinical significance. The study followed the Joanna Briggs Institute guidelines, utilizing a structured protocol based on the population, concept, and context (PCC) framework. Five databases were searched, and preclinical and clinical studies on CBD pharmacokinetic and pharmacodynamic interactions were included, with publications in English, Portuguese, or Spanish. Out of 136 studies analyzed, 91.91% were published after 2011, reflecting a sharp rise in interest in this area. A total of 271 interactions were identified, with 203 related to pharmacokinetics, primarily involving metabolism mediated by cytochrome P450 (CYP) enzymes, and 68 linked to pharmacodynamics, including additive effects such as sedation. Among the most relevant findings, CBD was shown to inhibit CYP enzymes like CYP3A4 and CYP2C19, potentially increasing plasma levels of co-administered drugs. However, only 5.15% of studies evaluated the clinical relevance of these interactions, indicating a substantial gap in knowledge regarding their safety implications. This review highlights the urgent need for rigorous clinical research to determine the clinical significance of CBD-drug interactions, particularly in patients undergoing polypharmacy. Understanding these interactions is crucial for optimizing therapeutic outcomes, minimizing adverse effects, and enabling safer clinical use of CBD in diverse treatment regimens.