Cannabidiol (CBD) is one of many cannabinoid molecules produced by Cannabis, second only to THC in abundance. These plant-derived cannabinoids, or phytocannabinoids (phyto = plant in Greek), are characterized by their ability to act on the cannabinoid receptors that are part of our endocannabinoid system. While THC is the principal psychoactive component of Cannabis and has certain medical uses, CBD stands out because it is both non-intoxicating and displays a broad range of potential medical applications. These properties make it especially attractive as a therapeutic agent.
Evaluating CBD Clinical Trial Evidence
Perhaps the most remarkable thing about CBD is the sheer number and variety of its potential therapeutic applications. It is important to recognize that each application may be supported by different levels of evidence. These range from ongoing clinical trials evaluating its efficacy in the treatment of human disorders, to animal studies investigating its behavioral and physiological effects, to in vitro work (test tube experiments) measuring its pharmacological interactions and mechanisms of action. Each type of study comes with its own strengths and weaknesses.
Clinical trials allow us to draw conclusions about the safety and effectiveness of potential therapeutic agents in humans, while animal studies and in vitroexperiments allow researchers to explore their biological actions in greater detail. However, because the latter class of studies are not conducted in humans, the results don’t always lead to the clinical application that we hope for—the majority of drugs that start in human clinical trials never become approved. Nonetheless, animal studies provide us with a strong foundation of biological knowledge, and are where the initial breakthroughs in research are made.
Why Does CBD Have So Many Potential Therapeutic Benefits?
CBD is famous for the promise it holds for treating treatment-resistant forms of childhood epilepsy. A number of clinical trials, testing the efficacy of CBD in human epilepsy patients, are currently underway. But there is also evidence, mainly from animal studies and in vitro experiments, that CBD may have neuroprotective, anti-inflammatory and analgesic (pain-relieving) properties, and potential therapeutic value in the treatment of motivational disorders like depression, anxiety, and addiction.
What’s the biological basis for this wide range of potential medical uses? A key part of the answer lies in CBD’s promiscuous pharmacology—its ability to influence a wide range of receptor systems in the brain and body, including not only cannabinoid receptors but a host of others.