You might think it’s “just” marijuana, but the cannabis plant is actually made up of more than 560 compounds, more than 100 of which are considered cannabinoids. And there’s a reason people have been using this plant for more than 1,000 years for its feel-good and medicinal properties. These chemicals have a similar structure to the molecules our bodies naturally make and operate in the endocannabinoid system, a cellular network that’s involved in regulating sleep, pain, inflammatory and immune responses, and hunger.
The two most prominent cannabinoids in marijuana — and most studied for their effects in the human body — are delta-9-tetrahydrocannabinol, or THC, and cannabidiol, or CBD. Both have therapeutic potential for various health concerns, but there’s still a lot we don’t know.
The goal, then, is to maximize the benefits and minimize the risks, said Nephi Stella, a professor in the departments of pharmacology, psychiatry and behavioral sciences at the University of Washington School of Medicine, and author of a review article in Neuron about the similarities and differences between THC and CBD.
Researching cannabinoids in marijuana has been difficult historically because it’s been classified as a Schedule I substance, meaning it has “no currently accepted medical use and a high potential for abuse, according to the U.S. Drug Enforcement Administration. With the recent recategorization of marijuana to a Schedule III drug, though, studies will become easier to conduct.
In the meantime, here’s a closer look at what we know about how they differ and what they can do.
What to know about THC
THC is the primary psychoactive compound in cannabis, the one that produces a high.
THC activates specific receptors in the endocannabinoid system called CB1 receptors, which are prominent in our brains, said Ryan Vandrey, a professor in the department of psychiatry and behavioral sciences at Johns Hopkins University School of Medicine and a researcher in the university’s Cannabis Science Lab.
It’s that activation of CB1 receptors that makes THC intoxicating, Stella said.
THC is linked with certain benefits, including easing chronic pain and helping with sleep. Synthetic forms of THC are also used in Food and Drug Administration-approved medications to treat nausea and vomiting from chemotherapy, as well as weight loss and loss of appetite in people with HIV/AIDS.
In a recent study done in Germany on people with post-traumatic stress disorder and frequent, intense nightmares, more than a third of the patients treated with a medication containing THC reported that they no longer experienced nightmares after 10 weeks.
Like anything used for therapeutic purposes, there are potential risks.
Frequent use of high doses of THC-rich cannabis can increase your chances of developing cannabinoid hyperemesis syndrome, or severe cyclic vomiting tied to cannabis use.
It’s estimated that up to 30 percent of people who use cannabis may meet criteria for cannabis use disorder, which is characterized by building tolerance to cannabis, compulsive behavior and a loss of control over cannabis use.
THC is also linked to an earlier diagnosis of psychosis and schizophrenia in those who are genetically predisposed or otherwise at a high risk, and is associated with worse symptoms and more relapses of both. Starting to use cannabis at an earlier age has been shown to up this risk.
What to know about CBD
CBD, or cannabidiol, doesn’t induce a high “and doesn’t have the same abuse liability as THC,” Vandrey said. It affects a number of brain receptors, but we’ve pinpointed only a few so far, and there’s more to understand about how CBD works in the brain.
For example, we know it affects a receptor called transient receptor potential vanilloid (TRPV) 1, which is involved in seizures, making it useful as an epilepsy treatment, Stella said. “When CBD was approved by the FDA as an antiepileptic, that was a huge landmark for the field,” Stella said, referring to the 2020 approval of an oral CBD formulation for seizures. How it works exactly is unclear, but the leading theory is that it may desensitize some neuron activity. We also know CBD can affect serotonin receptors in the brain, Vandrey added, which affects mood.
Additionally, CBD is being studied for possible benefits for substance use disorder and pain management, without the risk of intoxication or abuse that other drugs have. This benefit is particularly attractive for people with chronic pain, Stella said, who need a way to constantly manage their symptoms without getting high.
Emerging evidence suggests CBD may have potential benefits for improving social interactions and sleep in people with autism and easing anxiety symptoms, although more and larger studies are needed, Vandrey said.
CBD can work synergistically with THC. Many medical CBD products also contain low doses of THC. Research is starting to look into this ratio more, in hopes of identifying how much THC in relation to CBD might optimize the benefits (and reduce any negative effects) on something like sleep or pain, Stella said.
Keep in mind that frequent, high doses of CBD may hurt the liver. Plus, CBD could interfere with other medications you’re taking, including antidepressants, pain medications and blood thinners. “A lot of people are unaware of that and think ‘CBD is safe, it’s legal, I can just use it without concern,’” Vandrey said. “But if you also happen to be taking a medication that can cause adverse effects, and CBD inhibits its metabolism, you can get overexposed to that medication and experience unwanted and unexpected side effects.”
Safety concerns remain about both
CBD is federally legal when derived from hemp, a version of the marijuana plant that contains very little THC. That means you can find it outside of official medical- or recreational-use dispensaries, including at gas stations, convenience stores and smoke shops. This is concerning to experts because these products are “very poorly regulated,” Vandrey said.
If you’re getting CBD or THC products from unregulated sources, they could be contaminated with other drugs or toxins such as heavy metals. There could also be no actual CBD or THC in there, Vandrey said.
If the CBD market were more closely regulated, the products might be more helpful, as the dose you take can make the difference between relief or no relief, Stella said. It’s always a good idea to talk to a health care provider before starting any new medication or supplement, including CBD or THC, he added.
Stella remains hopeful about the potential of cannabis-derived medications to transform treatment options for health conditions and concerns that previously haven’t had many effective options. “Cannabis is not only for potheads,” he said. “It’s actually a transformative new medicine. That’s how we’re going to talk about it in the future.”
The post CBD vs. THC: What’s the difference between these cannabis components? appeared first on Washington Post.
