Please use this link to access this publication. Abstract Purpose  Increased cannabis use and recent drug approvals pose new challenges for avoiding drug interactions between cannabis products and conventional medications. This review aims to identify drug-metabolizing enzymes and drug transporters that are affected by concurrent cannabis use and, conversely, those co-prescribed medications that may alter the exposure to one or more cannabinoids. Methods  A systematic literature search was conducted utilizing the Google Scholar search engine and MEDLINE (PubMed) database through March 2019. All articles describing in vitro or clinical studies of cannabis drug interaction potential were retrieved for review. Additional articles of interest were...

Abstract Introduction: Treatment with cannabis extracts for a variety of diseases has gained popularity. However, differences in herb-drug interaction potential of extracts from different plant sources are poorly understood. In this study, we provide a characterization of cannabis extracts prepared from four cannabis chemotypes and an in vitro assessment of their Cytochrome P450 (CYP)-mediated herb-drug interaction profiles. Methods: Plant extracts were either commercially obtained or prepared using ethanol as solvent, followed by overnight decarboxylation in a reflux condenser system. The extracts were characterized for their cannabinoid content using NMR and HPLC-PDA-ELSD-ESIMS. CYP inhibition studies with the cannabis extracts and pure cannabinoids (tetrahydrocannabinol [THC] and cannabidiol [CBD])...

Abstract This Phase I study aimed to assess the potential drug-drug interactions (pharmacokinetic [PK] and safety profile) of Δ9-tetrahydrocannabinol (THC)/cannabidiol (CBD) oromucosal spray (Sativex ®, nabiximols) in combination with cytochrome P450 (CYP450) inducer (rifampicin) or inhibitors (ketoconazole or omeprazole). Thirty-six healthy male subjects were divided into three groups of 12, and then randomized to one of two treatment sequences per group. Subjects received four sprays of THC/CBD (10.8/10 mg) alongside single doses of the CYP3A and 2C19 inducer rifampicin (600 mg), CYP3A inhibitor ketoconazole (400 mg) or CYP2C19 inhibitor omeprazole (40 mg). Plasma samples were analyzed for CBD, THC and its metabolite 11-hydroxy-THC (11-OH-THC). A...

Please use this link to access this publication. ABSTRACT Introduction: To determine, via narrative, non-systematic review of pre-clinical and clinical studies, whether the effect of cannabis on hepatic biotransformation pathways would be predicted to result in clinically significant drug-drug interactions (DDIs) with commonly prescribed psychotropic agents. Areas covered: A non-systematic literature search was conducted using the following databases: PubMed, PsycInfo, and Scopus from inception to January 2017. The search term cannabis was cross-referenced with the terms drug interactions, cytochrome, cannabinoids, cannabidiol, and medical marijuana. Pharmacological, molecular, and physiologic studies evaluating the pharmacokinetics of Δ9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD), both in vitro and in vivo, were included. Bibliographies were also manually searched...

Abstract Objective Cannabidiol (CBD) has been approved by the US Food and Drug Administration (FDA) to treat intractable childhood epilepsies, such as Dravet syndrome and Lennox-Gastaut syndrome. However, the intrinsic anticonvulsant activity of CBD has been questioned due to a pharmacokinetic interaction between CBD and a first-line medication, clobazam. This recognized interaction has led to speculation that the anticonvulsant efficacy of CBD may simply reflect CBD augmenting clobazam exposure. The present study aimed to address the nature of the interaction between CBD and clobazam. Methods We examined whether CBD inhibits human CYP3A4 and CYP2C19 mediated metabolism of clobazam and N-desmethylclobazam (N-CLB), respectively, and performed studies...

Abstract Cannabidiol (CBD), a major purified nonpsychoactive component of cannabis with anticonvulsant properties, was approved by the U.S. Food and Drug Administration (FDA) in June 2018 as an adjuvant treatment for refractory epilepsy (Epidiolex; GW Pharmaceuticals). CBD is metabolized by cytochrome P450 (CYP)3A4 and CYP2C19 with a growing body of evidence suggesting it is also a potent inhibitor of these pathways. We report for the first time a significant drug-drug interaction between the purified CBD product and tacrolimus. A participant in a CBD clinical trial for epilepsy who was also receiving tacrolimus showed an approximately 3-fold increase in dose-normalized tacrolimus concentrations while receiving 2000-2900 mg/day...

Abstract Introduction Anxiogenic and anxiolytic effects of cannabinoids are mediated by different mechanisms, including neural signaling via cannabinoid receptors (CBRs) and nicotinic cholinergic receptors (nAChRs). This study examined the effects of prior nicotine (the psychoactive component in tobacco) exposure on behavioral sensitivity to delta-9-tetrahydrocannabinol (THC; the psychoactive component of cannabis) challenge in animals. Methods Male and female adult Sprague-Dawley rats (N = 96) were injected daily with nicotine (1 mg/kg, i.p.) or vehicle for 14 days, followed by a 14-day drug-free period. On test day, rats were injected with THC (0.5, 2.0, or 5.0 mg/kg, i.p.) or vehicle and anxiety-related behavior was assessed in the emergence (EM), elevated plus...

Abstract Cannabidiol (CBD) is ubiquitous in state-based medical cannabis programs and consumer products for complementary health or recreational use. CBD has intrinsic pharmacologic effects and associated adverse drug events (ADEs) along with the potential for pharmacokinetic and pharmacodynamic drug–drug interactions (DDIs). Given CBD use among patients with complex conditions and treatment regimens, as well as its expanded consumer use, awareness of potential safety issues with CBD is needed. Prescribing information for federally approved products containing CBD were reviewed. Data on ADEs and DDIs were extracted and summarized. Nearly one-half of CBD users experienced ADEs, which displayed a general dose-response relationship. Common ADEs include transaminase...

Abstract Medical cannabis use is increasing worldwide. Clinicians are commonly asked by patients to provide guidance on its safety and efficacy. Although there has been an increase in research on the role of medical cannabis for a number of different conditions, we found that there was a paucity of clear safety guidance on its use. We aim to address this issue by answering two pertinent clinician safety questions: 1 Can medical cannabis be safely used in this patient? 2. What strategies can be used to ensure that any harms from medical cannabis are mitigated? To address these questions, we reviewed available evidence and provided...

Abstract Although prescribing information (PI) is often the initial source of information when identifying potential drug-drug interactions, it may only provide a limited number of exemplars or only reference a class of medications without providing any specific medication examples. In the case of medical cannabis and medicinal cannabinoids, this is further complicated by the fact that the increased therapeutic use of marijuana extracts and cannabidiol oil will not have regulatory agency approved PI. The objective of this study was to provide a detailed and comprehensive drug-drug interaction list that is aligned with cannabinoid manufacturer PI. The cannabinoid drug-drug interaction information is listed in this...