By now you’ve certainly heard about cannabidiol, better known as CBD, a product derived from cannabis or hemp.
CBD vendors at trade shows are consistently mobbed by curious doctors, and new companies are opening almost every week. Accordingly, you might be wondering if it’s safe, if it’s effective, and if it’s legal.
The answers to these questions are clarifying as researchers and governments grapple with the burgeoning science and evidence behind CBD, and it’s safe to say that we’ll know more tomorrow than we do today. That said, it’s time to take a close look at where we stand with this promising supplement.
A rocky road
Briefly, we know from archeological discoveries that people have been using the cannabis plant for medical and possibly religious purposes since at least 500 BC (if not earlier), and our word “assassin” comes from an Arabic word (hasisi) meaning “hashish-eater,” entering English around AD 500. America’s Founding Fathers, including George Washington and Thomas Jefferson, grew hemp on their plantations, and by around the mid-1800s various medicinal preparations of cannabis were appearing in pharmacies as remedies for nausea and vomiting
In the early 1900s, Mexican immigrants
introduced the practice of smoking marijuana, and it became somewhat popular
until it was banned at the state level beginning in 1911. By 1933, more than
half the states had outlawed cannabis, and it wasn’t until 1973 that the long
process of decriminalization began—which is still ongoing.
With the passage of Proposition 215 in 1996,
cannabis for medical use was legalized in California and over the next 20 years
more than half the states followed suit. The federal government, however, in
passing the Controlled Substances Act in 1970, officially prohibited cannabis
for any use—including medicinal—by listing it as a Schedule I drug (one having
no recognized medical use and a high potential for abuse).
This gets us to where things stand today. The Farm Bill passage changes the status of CBD in the eyes of the federal law. CBD is no longer in a legal gray area, opening up the possibilities immensely for new research to be done. However, medical applications of cannabis and CBD are currently still lacking the robust academic studies needed to uncover with certainty how they work because of its past legal limbo. It was previously difficult for researchers to obtain and test theories in large cohort trials.¹ Good- to high-quality studies do exist, however, with evidence that cannabis and cannabinoids have modest to moderate therapeutic value for “treating chronic pain, chemotherapy-induced nausea and vomiting, and patient-reported symptoms of spasticity associated with multiple sclerosis.”¹
Wait, back up
The previous sections mention cannabis, cannabidiol, marijuana and hemp. These terms are not freely interchangeable. Some explanation is in order
Cannabis is the name of the
plant from which marijuana and hemp derive. It comes in two varieties, Cannabis
sativa and Cannabis indica. Although it is commonly believed
that the sativa variety is more euphoric and the indica form more relaxing,
there is little to no evidence that this is true. Rather, it’s the
cannabinoids, terpenes and flavones in a strain that give it its medicinal
properties.2 The cross-breeding of plants has led to a general homogenization
The type of cannabis called marijuana
is cultivated to maximize the amount of tetrahydrocannabinol (THC) it
contains, which is what gives it psychoactive properties.
On the other hand, the cannabis plant known as hemp
contains almost no THC whatsoever, but it can be rich in CBD. Until now, hemp
has mainly been an industry product used for its fiber.3 Confusion among
lawmakers led to hemp being classified as a Schedule I drug along with
marijuana. Commercially available CBD contains 0.3 percent THC or less, meaning
it has no psychoactive properties.
The endocannabinoid system (ECS) is
common to all mammals, and it consists of neurotransmitters and receptors found
throughout the central and peripheral nervous systems. It acquired its name
because it is affected by cannabis, but the body contains its own
endocannabinoids, which are released by voluntary exercise—it’s what runners
experience (the “runner’s high”).
THC affects the endocannabinoid system by
binding to CB1 and CB2 receptors, leading to euphoric effects, in addition to
impacting appetite and reducing nausea.4 CBD, on the other hand, is an
agonist at TRP channels and antagonizes
GPR55. In effect, it suppresses the uptake of the body’s own endocannabinoids,
somewhat analogous to the action of selective serotonin reuptake inhibitors
(SSRIs). CBD stops the body’s absorption of anandamide, which regulates pain.
And CBD is widely known for its anti-seizure properties, pain and inflammation
moderation, and it’s potentially therapeutic with respect to anorexia,
metabolic syndrome-related disorders, and Parkinson’s disease, among other
Terpenoids are common to many herbs, such as menthol,
camphor, the ginkgolide and bilobalide in Ginko
biloba, and are common in citrus
fruits. The curcuminoids in turmeric are well-known to herbalists. Those found
in cannabis include caryophyllene, which has anti-fungal and anti-inflammatory
properties, and gives marijuana its characteristic aroma. It’s what
drug-sniffing dogs detect. Phytol is a diterpene that increases GABA
expression, which has a mild sedative effect.5 Terpenoids have powerful effects
on pain cessation as well.6
The “entourage effect” was
originally coined to refer to the activity of the body’s native
endocannabinoids, but more recently it has been applied to the concept that
cannabis plants contain a mixture of cannabinoids, terpenoids and
phytochemicals. It is theorized that CBD isolates may not work as effectively
as full-spectrum products as the “entourage” of components could have
synergistic properties. More research is needed to confirm or disprove this
A review of the literature finds a range
of claims for medical marijuana and CBD. Before recommending CBD to patients or
advising them regarding their own use, weigh the evidence carefully regarding
what is known and what is merely believed. These are early days and
evidence-based research is ongoing.
Antipsychotic: Drugs for
patients who experience symptoms along the schizophrenic spectrum are generally
treated with drugs that target the dopamine D2 receptors. A study of the effect
of CBD on psychosis found that it can be as effective as the antipsychotic
aripiprazole, and that it indeed functions as a dopamine D2 agonist.6
Anti-seizure: CBD is well-known
for its usefulness in controlling seizure disorders. In fact, one of the first
companies to market CBD oil to consumers was founded to treat a child who
wasn’t being helped by traditional pharmacotherapy. Its effectiveness in this
regard was instrumental in changing laws in many states to legalize CBD or make
it available to medical patients. Earlier this year, the FDA approved a
purified CBD product called Epidiolex for treatment of severe epilepsy.7 It’s
notable that the drug was approved on a fast-track basis.
Anti-anxiety: Most users of CBD report it having a calming
effect and attest to feelings of general wellness and relaxation. This may make
it an appropriate treatment for patients with neuropsychiatric disorders, such
as panic disorder (PD), generalized anxiety disorder (GAD), post-traumatic
stress disorder (PTSD), social anxiety disorder (SAD), and obsessive-compulsive
disorder (OCD).8 Standard treatments for these types of patients is with SSRIs
and benzodiazepines, which convey considerable risks of side effects and
Antioxidant: As mentioned above,
CBD has anti-fungal properties and is
protective in a number of ways, including anti-inflammatory effects from the
action of several of its components. It has been shown to suppress the transcription
of many proinflammatory genes.9 One study found that THC extracts had limited
effect in controlling cancer cells, but CBD was highly effective at preventing
cell growth and causing apoptosis (cell death) in cervical cancer lines, and
may prove useful in inhibiting prostate and breast cancer growth.10
More research is needed in this area.
Analgesic: One way that CBD
appears to mitigate pain is by potentiating glycine receptors, glycine being an
inhibitory neurotransmitter in the brain and spinal cord.11
Virtually every drug developed for treating chronic, inflammatory and
neuropathic pain comes with adverse side effects. Lab studies have found that
CBD is not only effective in this regard, but it appears to have no
tolerance-building aspect. Unlike with many drugs aimed at long-term pain
management, CBD remains effective at a standard dose over time.
But is it legal?
This has always been the overarching issue
regarding cannabidiol because it has existed in a legal gray area for most of
its existence. The constant flux of legality is often the reason DCs are wary
of recommending it to their patients, despite its numerous benefits. However
with the passing of the Agriculture and Nutritional Act or Farm Bill,
industrial hemp is now legalized. This cannabis strain is critical to the CBD
industry. This removes hemp and any hemp derivative from the Controlled
Substances Act, legally separating it from marijuana and putting its
supervision under the Department of Agriculture.
“The passing of the 2018 Farm Bill is a huge victory for natural medicine in the United States and the supplement industry. We will now be able to safely and effectively provide hemp/CBD products to people in all 50 states without any doubt of legality,” said S. Michael Lioon, co-founder of TruGen3. “Patients suffering from illnesses such as inflammation, anxiety, seizures, sleep, and neurological conditions will now be able to legally obtain an all natural product to support their conditions. And for companies with hemp/CBD products, we will now be able to market our products across all media platforms without any restrictions. This is really a win for all parties involved.”
Bill is a huge win for the CBD industry, but does not create a completely free
system where anyone can grow hemp whenever or wherever they want. In order to
be classified as industrial hemp, it cannot contain more than 0.3 percent THC.
States will also have submit plans to license and regulate hemp to the USDA
before operations can commence. But as a DC, you can rest easy knowing that
recommending CBD is no longer in legal limbo.
Dosage and protocols for use are largely patient-dependent. Experts advise
“starting low and slow.”12 In one study, participants were given
varying doses of CBD prior to giving a public talk—traditionally a highly
stressful experience for most people. It was found that increasing the amount
of CBD reduced the speakers’ anxiety up to a point, beyond which it had the
opposite effect.13 Therefore, patients should self-titrate to the amount
medically efficacious, and sustain their dosage to that degree.
The landscape regarding what is known about CBD
and what its therapeutic applications are in a continuous state of flux. At the
moment, it appears to be an effective treatment for a variety of conditions,
and it has no apparent drug-supplement interactions, tolerance-building
effects, or overdose potential. It is extremely safe and well tolerated.
Whether you recommend it to patients or not, CBD should be on your radar as a
promising supplement for numerous acute and chronic health conditions.
Daniel Sosnoski is the former editor-in-chief of Chiropractic Economics.
1 National Academies of Sciences, Engineering, and Medicine. “Therapeutic Effects of Cannabis and Cannabinoids.” In: The Health Effects of Cannabis and Cannabinoids: The Current State of Evidence and Recommendations for Research. Washington, DC: The National Academies Press; 2017: 85-127.
2 Pellati F, Brighenti V, Sperlea J. New Methods for the Comprehensive Analysis of Bioactive Compounds in Cannabis sativa L. (hemp). Molecules. 2018;23(10):pii E2639.
3 Pollio A. The Name of Cannabis: A Short Guide for Nonbotanists. Cannabis Cannabinoid Res. 2016;1(1):234-238.
4 Kaur R1, Ambwani SR, Singh S. Endocannabinoid System: A Multi-Facet Therapeutic Target. Curr Clin Pharmacol. 2016;11(2):110-7.
5 Rosenberg EC, Tsien RW, Whalley BJ, Devinsky O. Cannabinoids and Epilepsy. Neurotherapeutics. 2015;12(4): 747-768.
6 Russo EB. Taming THC: potential cannabis synergy and phytocannabinoid-terpenoid entourage effects. Br J Pharmacol. 2011;163(7): 1344-1364.
7 Seeman P. Cannabidiol is a partial agonist at dopamine D2High receptors, predicting its antipsychotic clinical dose. Transl Psychiatry. 2016;6(10): e920.
8 U.S. Food & Drug Administration. “FDA approves first drug comprised of an active ingredient derived from marijuana to treat rare, severe forms of epilepsy.” U.S. Dept. of Health and Human Services. https://www.fda.gov/newsevents/newsroom/pressannouncements/ucm611046.htm. Published June 2018. Accessed Nov. 2018
9 Blessing EM, Steenkamp MM, Manzanares J, Marmar CR. Cannabidiol as a Potential Treatment for Anxiety Disorders. Neurotherapeutics. 2015;12(4):825-36.
10 Kozela E, Juknat A, Gao F, et al. Pathways and gene networks mediating the regulatory effects of cannabidiol, a nonpsychoactive cannabinoid, in autoimmune T cells. J Neuroinflammation. 2016;13(1):136.
11 Sindiswa T. et al. Cannabidiol rather than Cannabis sativa extracts inhibit cell growth and induce apoptosis in cervical cancer cells. BMC Complement Altern Med. 2016;16(1):335.
12 Xiong W, Cui T, Cheng K, et al. Cannabinoids suppress inflammatory and neuropathic pain by targeting α3 glycine receptors. J Exp Med. 2012;209(6):1121-1134.
13 Stankiewicz A. “Cannabidiol is a remarkably versatile option for wellness.” Chiropractic Economics. https://www.chiroeco.com/cannabidiol-2. Published Sept. 2018. Accessed Nov. 2018.
14 Bergamaschi MM, Queiroz RH, Chagas MH, et al. Cannabidiol reduces the anxiety induced by simulated public speaking in treatment-naïve social phobia patients. Neuropsychopharmacology. 2011;36(6):1219-26.