Laboratory evidence indicated that cannabidiol may reduce THC clearance, increasing plasma concentrations which may raise THC availability to receptors and enhance its effect in a dose-dependent manner. In vitro, cannabidiol inhibited receptors affecting the activity of voltage-dependent sodium and potassium channels, which may affect neural activity. A small clinical trial reported that CBD partially inhibited the CYP2C-catalyzed hydroxylation of THC to 11-OH-THC. Little is known about potential drug interactions, but CBD-mediates a decrease in clobazam metabolism.
Cannabidiol can be taken into the body in multiple ways, including by inhalation of cannabis smoke or vapor, as an aerosol spray into the cheek, and by mouth. It may be supplied as CBD oil containing only CBD as the active ingredient (no included tetrahydrocannabinol [THC] or terpenes), a full-plant CBD-dominant hemp extract oil, capsules, dried cannabis, or as a prescription liquid solution. CBD does not have the same psychoactivity as THC, and may change the effects of THC on the body if both are present. As of 2018, the mechanism of action for its biological effects has not been determined.
In 2019, the European Commission announced that CBD and other cannabinoids would be classified as "novel foods", meaning that CBD products would require authorization under the EU Novel Food Regulation stating: because "this product was not used as a food or food ingredient before 15 May 1997, before it may be placed on the market in the EU as a food or food ingredient, a safety assessment under the Novel Food Regulation is required." The recommendation – applying to CBD extracts, synthesized CBD, and all CBD products, including CBD oil – was scheduled for a final ruling by the European Commission in March 2019. If approved, manufacturers of CBD products would be required to conduct safety tests and prove safe consumption, indicating that CBD products would not be eligible for legal commerce until at least 2021.
Vaping is the act of inhaling and exhaling the aerosol, often referred to as vapor, which is produced by an e-cigarette or similar device. The term is used because e-cigarettes do not produce tobacco smoke, but rather an aerosol, often mistaken for water vapor, that actually consists of fine particles. Many of these particles contain varying amounts of toxic chemicals, which have been linked to cancer, as well as respiratory and heart disease.