Pharmacokinetic interaction: Sativex + omeprazole (Sativex-Omeprazole DDI)

Pharmacokinetic interaction: Sativex + omeprazole refers to the clinical evaluation of how the proton pump inhibitor omeprazole influences the absorption, distribution, metabolism, and excretion of Sativex (nabiximols). Sativex is an oromucosal spray containing a 1:1 ratio of delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD), primarily indicated for the treatment of spasticity in multiple sclerosis (Stott et al., 2013). Both THC and CBD undergo extensive hepatic metabolism via the cytochrome P450 enzyme system, specifically involving the CYP3A4 and CYP2C19 isoforms. Omeprazole is a well-characterized inhibitor of CYP2C19, leading to concerns that its co-administration might elevate plasma levels of cannabinoids and increase the risk of adverse effects (Sativex SmPC, 2023). However, clinical pharmacokinetic studies have demonstrated that omeprazole does not produce a statistically significant or clinically relevant change in the peak plasma concentrations (Cmax) or total exposure (AUC) of THC or CBD (Stott et al., 2013). This lack of interaction is attributed to the presence of multiple metabolic pathways for cannabinoids, which allows for compensatory clearance when one pathway is inhibited. Consequently, Sativex can generally be administered alongside omeprazole without the need for specific dose adjustments, although patients should always be monitored for altered sensitivity to cannabinoid effects.

Other names

Sativex and Omeprazole Drug-Drug InteractionNabiximols-Omeprazole InteractionCYP2C19-mediated interaction of Sativex and Omeprazole

Omeprazole acts as a reversible inhibitor of the Cytochrome P450 2C19 (CYP2C19) enzyme, which is one of the pathways responsible for the metabolism of cannabidiol (CBD) and tetrahydrocannabinol (THC) found in Sativex.