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Does Cannabidiol Protect Against Adverse Psychological Effects of THC?

This article was submitted to Addictive Disorders and Behavioral Dyscontrol, a section of the journal Frontiers in Psychiatry.

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The recreational use of cannabis can have persistent adverse effects on mental health. Delta-9-tetrahydrocannabinol (THC) is the main psychoactive constituent of cannabis, and most, if not all, of the effects associated with the use of cannabis are caused by THC. Recent studies have suggested a possible protective effect of another cannabinoid, cannabidiol (CBD). A literature search was performed in the bibliographic databases PubMed, PsycINFO, and Web of Science using the keyword “cannabidiol.” After removing duplicate entries, 1295 unique titles remained. Based on the titles and abstracts, an initial selection was made. The reference lists of the publications identified in this manner were examined for additional references. Cannabis is not a safe drug. Depending on how often someone uses, the age of onset, the potency of the cannabis that is used and someone’s individual sensitivity, the recreational use of cannabis may cause permanent psychological disorders. Most recreational users will never be faced with such persistent mental illness, but in some individuals cannabis use leads to undesirable effects: cognitive impairment, anxiety, paranoia, and increased risks of developing chronic psychosis or drug addiction. Studies examining the protective effects of CBD have shown that CBD can counteract the negative effects of THC. However, the question remains of how the laboratory results translate to the types of cannabis that are encountered by real-world recreational users.

Keywords: tetrahydrocannabinol, cannabidiol, cannabis, psychosis, anxiety, drug dependence, cognition

Tetrahydrocannabinol (THC) is the main psychoactive substance in cannabis. Cannabidiol (CBD) is a cannabinoid that appears in cannabis resin but rarely in herbal cannabis. In recent years, many positive attributes have been ascribed to CBD. Is cannabis that contains CBD less harmful than cannabis without CBD? Are people who smoke cannabis resin, therefore, less susceptible to psychosis or less likely to become addicted than are people who smoke herbal marijuana? In this article, several of the health aspects of CBD will be reviewed. The article will focus on the role played by CBD in contributing to the psychological effects that are experienced during recreational cannabis use.


Cannabis sativa contains more than 80 different cannabinoids, of which THC is principally responsible for the pharmacological actions, including the psychoactive effects. THC binds to specific proteins in the brain – the cannabinoid receptors (CB-Rs) (1). Two different receptors have been discovered: the CB1 and CB2 receptors (2, 3). CB1-R is mainly found in the central nervous system (CNS); CB2-R is predominantly present in the immune system (3–5). Endocannabinoids are naturally occurring substances that attach to these receptors (6–8).

Cannabinoid receptors, endocannabinoids, and the enzymes involved in the synthesis and degradation of these substances together form the endocannabinoid system (9). The activation of the CB-Rs affects the actions of various neurotransmitters, such as acetylcholine, dopamine, GABA, glutamate, serotonin, norepinephrine, and endogenous opioids (10, 11). Under normal physiological circumstances, CB-Rs are activated by endocannabinoids (12). The activation of CB-Rs by endocannabinoids inhibits excessive neurotransmitter release. Endocannabinoids are lipid-soluble compounds, which prevent them from traveling long distances within the brain. As a consequence of this feature, endocannabinoids are ideally suited for small-scale, local physiological processes (13).

Tetrahydrocannabinol mimics the effect of endocannabinoids. In contrast to these substances, THC is not rapidly broken down at the site of operation, and it not only works at specific locations but simultaneously activates all CB receptors throughout the brain (14).

The mechanisms by which CBD exerts its effect are not precisely known, but it is clear that the pharmacological actions of CBD follow from many different mechanisms [for reviews, see Ref. (15, 16)]. CBD weakly binds to CB-Rs but is capable of antagonizing the effects of THC, even when the former is present in low doses. By inhibiting the degradation of the endogenous cannabinoid anandamide, CBD intensifies, and prolongs its effect (17). The (extended) presence of anandamide prevents THC from interacting with CB-Rs. CBD also interacts with several other recently discovered CB-Rs, and it is an agonist for the 5-HT1A receptor (18, 19), which may explain some of the antipsychotic and anxiolytic effects of CBD (20). Through its effect on intracellular calcium concentrations, CBD might protect neurons against the possible neurotoxic effects of THC (21). CBD itself has almost no effect on normal physiological processes. Only when a stimulus (such as pain or a shock reaction) or another cannabinoid (such as THC) upsets the normal “tone” of the endocannabinoid system is the effect of CBD expressed (12).

The amount of CBD administered, the ratio of CBD to THC and the timing of administration all seem to be important in determining the possible effects of CBD (22, 23). Most clinical studies on the effects of CBD are not relevant for generalizing to the effects of CBD in “recreational” cannabis users. In many of these studies, the doses that have been used are not relevant to the situation typically encountered by recreational cannabis users.

Clinical research has focused on the physical effects of cannabis use, such as pain relief, appetite promotion, and inflammation. For recreational cannabis users, the substance’s psychological effects are the most important. In many experimental studies, the routes of administration used for both THC and CBD are not comparable to the routes of administration found in recreational cannabis use. The high dosages of CBD that have been used in experimental studies increase the concentration of CBD in the blood to levels that can never be reached by smoking a joint. The method that is most comparable to smoking is exposure through a vaporizer, but little research has been conducted involving the administration of cannabis, THC, or CBD via a vaporizer (24, 25). Therefore, it is unknown to what extent the effects of a single administration procedure can be extrapolated to recreational cannabis users given such differences in usage patterns.

Toxicology of CBD

Research on the pharmacological and toxicological properties of CBD has been performed on different types of animals. In general, the metabolism of CBD in different species seems similar to that observed in humans, but some differences exist (26). It is possible that differences in metabolism and kinetics among different species have been responsible for some of the observed differences in pharmacological and toxicological effects.

Little research has focused on the safety and side effects of CBD in humans. However, several studies have described the effects of CBD for therapeutic applications in clinical trials. Only a few, generally mild side effects have been observed after administration of CBD in these human studies, though a wide range of effects over a wide dose range, including acute and chronic administration, have been examined. Few undesirable effects are reported, and tolerance for CBD does not seem to occur.

Based on an extensive literature review, Bergamaschi and colleagues concluded that CBD, to the extent that it has been studied, is a substance with low toxicity (27). Notably, however, the absence of harmful effects of CBD in humans has been described in research that was not primarily aimed at investigating these same side effects or toxicities of CBD. Because no specific research on these issues has been performed, it is currently impossible to draw conclusions about differences in toxicity between hashish and marijuana.

Chronic cannabis use is associated with psychiatric toxicity and cannabis has been implicated in the etiology of long-term psychiatric conditions (28). Several in vivo brain scanning techniques have been conducted to investigate whether chronic, heavy cannabis use leads to structural changes in the brain [for reviews, see Ref. (29, 30)]. The results of these studies have been relatively inconsistent. In general, no differences in total brain volume between cannabis users and non-users have been found. With respect to CB1 receptor concentrations in different parts of the brain, it can be expected that structural changes after chronic intensive cannabis use would most likely eventually be situated in the orbitofrontal cortex (OCC), the anterior cingulate cortex (ACC), the striatum, the amygdala, and the hippocampus (31–33). In some structural magnetic resonance imaging (sMRI) studies, reductions in the volumes of the hippocampus, the amygdala, and the cerebellum have been found in adult heavy cannabis users when compared with healthy controls (21, 34, 35). Using a PET scan technique, Wilson and colleagues found age-dependent morphological changes in early-onset cannabis users. In subjects who started their cannabis use before the age of 17, it has been found that the ratio of cortical gray to white matter is smaller when compared with subjects who had started using cannabis after their 17th birthdays (36). Structural abnormalities due to chronic cannabis use have been most consistently identified in the hippocampus (21, 34, 35). Using a voxel-based morphometry (VBM) approach, Demirakca and colleagues studied gray matter (GM) concentrations and volumes of the hippocampus in 11 chronic recreational cannabis users and 13 healthy controls and correlated their findings with THC and CBD measurements made from hair analyses. They found that cannabis users showed lower GM volume in the right anterior hippocampus. Higher THC and lower CBD were associated with this hippocampal volume reduction, suggesting neurotoxic effects of THC and neuroprotective effects of CBD.

The conflicting results among volumetric brain studies seem to result from differences in time span (e.g., age of onset), patterns of cannabis use (e.g., frequency, duration of use, cumulative lifetime use), and type of cannabis used (e.g., potency, CBD/THC ratio) (29, 30).

Psychological Effects

The effects of cannabis on psychological functioning mainly concern psychotic symptoms, anxiety, depression, cognitive functioning, and the potential for abuse and dependency. Several studies show that high doses of cannabis can provoke acute and transient psychotic reactions in both “healthy” users and in people with a certain predisposition for psychosis (37–39). These effects are dose-related (i.e., more THC produces a greater effect) and are stronger and longer-lasting in naive and occasional users than they are in frequent and transient cannabis users. Rottanburg and colleagues were the first to propose a protective effect of CBD on THC-induced psychosis. They suggested that the high incidence of cannabis-related psychosis among their patients occurred because cannabis variants in South Africa are more potent in terms of THC content and because they lack CBD (40).

As early as 1982, there were indications that the psychosis- and anxiety-inducing effects of THC can be suppressed by CBD (41, 42). Several other studies have found support for the antipsychotic effects of CBD. fMRI studies have shown that the effects of THC are correlated with a decrease in brain activity in the striatum. The striatum plays an important role in planning activities, modulating motor activity (movement), and performing cognitive tasks. CBD has been found to increase the activity in this brain area (43). Moreover, in other brain areas, the effects of CBD on neurological activity have been shown to be opposite those of THC.

In one Dutch and three English studies, associations between the consumption of certain types of cannabis and the occurrence of psychotic symptoms were reported (41–47). The results of these “naturalistic” studies suggest that CBD exerts a dampening effect on THC-induced psychotic symptoms. It is not clear for which CBD/THC ratio and for what minimum CBD concentration the protective effects of CBD may be expressed. The main features of these “naturalistic” studies are summarized in Table ​ Table1 1 .

Table 1

Summary of “naturalistic” studies in which the effects of cannabidiol and cannabis with a high dosis of THC on psychological functions have been investigated.

Reference Subjects THC/CBD Results Remarks
Di Forti et al. (47) “First-episode” psychiatric patients (n = 280) Self reported frequency and type of cannabis used The chance that high-potent cannabis (THC) has been used is higher among “first-episode” psychotic patients than among non-psychotics Also more frequent use in “first-episode” psychotic patients
Morgan and Curran (45) Cannabis users (n = 154) Grouping based on presence of THC and/or CBD in hair More psychotic symptoms among THC group in comparison with no THC group and in group with THC and CBD in hair THC might be psychotogenic and CBD might protect against this effect
Schubart et al. (48) Websurvey among cannabis users (n = 1877) Grouping based on self reported preference for type of cannabis Less psychotic symptoms in cannabis users who use cannabis with high level of CBD (hash) Personal communication with author (Schubart)
Morgan et al. (46) Cannabis users, at least once a month (n = 134) Choosing cannabis by cannabis user Acute effects on mood, psychotic symptoms, and cognition CBD attenuates the THC-induced memory impairment; CBD does not affect psychotomimetic symptoms
Morgan et al. (49) Recreational cannabis users (n = 54) versus daily users (n = 66) Measuring THC and CBD in hair THC increases possibility of negative psychotic symptoms, CBD antagonizes (part of) THC-induced effects

Longitudinal studies that have investigated the relationship between chronic cannabis use and the occurrence of psychosis have shown that cannabis use increases the risk of later psychotic symptoms and disorders by a factor of 2–3. The magnitude of the risk depends on the degree of exposure, the age of onset of cannabis use and the “vulnerability” of the user (50–52). No longitudinal studies have distinguished between the type of cannabis having been used, and no studies give an indication of the THC/CBD ratio.

One case-control study has shown an association between the occurrence of a first psychotic episode and the use of high-potency cannabis (skunk or sinsemilla) (47). Patients with psychotic symptoms had more frequently used skunk or sinsemilla cannabis instead of hashish than had non-patients. Patients experiencing first-episode psychosis were also more likely to be daily users of high-potency cannabis than were controls. This finding suggests that both the daily use and consumption of cannabis with a high-THC and low-CBD content increase the risk of developing psychosis.

Cannabis use can lower the age of a first psychotic episode (53, 54). Epidemiological and clinical studies suggest an adverse effect of cannabis use on the course of the disease in terms of relapse, exacerbation of symptoms and number of hospitalizations (38, 55–57). With the exception of a study by Di Forti et al. (47), no study has investigated the use of different types of cannabis in patients with a psychotic disorder. The extent to which the presence or absence of CBD in cannabis will influence the early occurrence of a first-episode psychosis or to what extent it will affect the course of the disease is, therefore, unknown.

Anxiety and panic attacks are the most commonly reported adverse reactions following the use of cannabis. Inexperience and use in a foreign environment play a major role (58). Though anxiety and panic attacks are often reported, many users take cannabis for its fear-inhibiting effects [for a review, see Ref. (59)]. THC seems to be responsible for the anxiogenic effects of cannabis [e.g., Ref. (58, 60, 61)].

By the early 1980s, it had been shown that THC led to a significant increase of acute anxiety symptoms, while CBD had no effect (42). When CBD and THC were administered together, the anxiogenic effect of THC was halved. This was an important indication that the anxiety-inducing effects of THC could be antagonized by CBD. The results from later studies, however, were inconsistent; the anxiety-reducing effect of CBD was not found in all subsequent studies. Ilan and colleagues investigated the contribution of THC and CBD to the subjective and behavioral effects of smoked marijuana (62). In their study, 23 healthy marijuana users were randomly assigned to a low- or a high-THC group and low or high levels of CBD. In the four sessions under blinded conditions, subjects smoked marijuana cigarettes containing placebo (no active cannabinoids) or cigarettes containing THC with low or high levels of CBD. Compared with the placebo, cannabis caused a slight short-term increase in anxiety symptoms (VAS). These effects were greatest in the high-THC condition and appeared to diminish when the CBD content was high, but this latter effect was not statistically significant. Because this increase in anxiety was generally mild and because not all subjects responded with fear, a follow-up analysis with only the anxious subjects was performed. There was a non-significant trend for less anxiety in the high- versus the low-CBD condition in subjects who reported higher levels of anxiety after smoking the joints. A reason for the absence of significant results in this study might be that neither the THC nor the CBD concentrations were high enough to have significant effects. In the studies in which anxiety-reducing effects were reported, high oral doses of CBD typically were involved. Cannabis that is used for recreational purposes does not contain such high amounts of CBD.

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People with cannabis dependence are more likely to suffer from an anxiety disorder and, in particular, from social anxiety disorder [for a review, see Ref. (58)].

So far, studies investigating the relationship between cannabis dependence and anxiety disorders have not clarified the nature of the relationship in question: does cannabis use lead to anxiety disorders or do anxiety disorders lead to the (over-) use of cannabis? There are no studies in which the relationship between cannabis use and anxiety disorders is examined and in which an inquiry about the type of cannabis used or its THC/CBD ratio is included.

In two experiments using patients suffering from social anxiety disorder along with healthy volunteers as controls, the subjects had to speak in front of a video camera, regardless of whether they were under the influence of CBD. In this experimental situation, CBD was effective in preventing symptoms of anxiety, both in healthy volunteers and in patients with social anxiety disorder (41, 63). CBD suppressed the symptoms of anxiety, similar to the action of the sedatives diazepam and ipsapirone. The main features of the studies on humans that have investigated the psychological effects of administering CBD (singularly or in combination with THC) are summarized in Table ​ Table2 2 .

Table 2

Overview of studies investigating the effect of cannabidiol or cannabidiol in combination with THC on psychological functions in humans. Studies in which cannabis extracts have been used are not included.

Reference Subjects Dosing THC/CBD Results Comments
Karniol et al. (64) Healthy volunteers (n = 40) 30 mg THC (oral); 15, 30 of 60 mg CBD (oral) or in combination with 30 mg THC (both oral) Antagonizing (part of) the THC-induced effects CBD decreased the anxiety component of THC effects; no effect of CBD alone
Hollister and Gillespie (65) Healthy volunteers (n = 30) 20 mg THC + 40 mg CBD (both oral) CBD delays onset of the effect of THC and prolongs the effects of THC
Dalton et al. (66) Healthy volunteers (n = 15) 25 μg/kg BW THC and 150 μg/kg BW CBD via smoking a joint CBD reduces euphoric effect of THC Only effective when CBD and THC are administered simultaneously
Hollister (67) Healthy volunteers (n = ?) CBD 5–30 mg i.v. No effects
Carlini and Cunha (68) Healthy volunteers Acute 600 mg CBD; 10 mg/kg/BW CBD 20 days CBD does not have psychological or physical effects Light drowsiness after CBD administration
Zuardi et al. (42) Healthy volunteers (n = 8) 0.5 mg/kg BW THC + 1 mg/kg BW CBD (both oral) CBD antagonizes psychological effects of THC (anxiety) CBD itself has no effect and does not antagonize the physical effects of THC (HR, BP)
Zuardi et al. (69) Treatment resistant schizophrenic patients (n = 3) CBD during 29 days upwards from 40 to 1280 mg/day (oral) CBD does not antagonize symptoms No side effects of CBD reported
Crippa et al. (70) Healthy volunteers (n = 10) CBD 400 mg oral Anxiolytic effects; light mental sedation SPECT results: effects in left amygdala-hippocampus complex radiating to hypothalamus
Leweke et al. (71) Psychiatric patients (n = 43) CBD oral 800 mg/day; during 4 weeks CBD more effective as antipychotic than amsulpride Less side effects of CBD than with amsulpride
Zuardi et al. (72) PD patients with psychoses CBD 150 mg/day; during 4 weeks CBD possibly effective for treatment of PD patients suffering from psychoses No significant side effects of CBD reported
Borgwardt et al. (73), Fusar-Poli et al. (74), Fusar-Poli et al. (75), Bhattacharyya et al. (76) a Healthy volunteers (n = 15) CBD oral 600 mg; 10 mg THC (not simultaneously); in comparison with placebo No effect in contrast with THC; CBD activates other brain areas than THC no effects of CBD in verbal learning task and no induction of psychotic symptoms No sedation and no inhibition of locomotion by CBD; THC induces psychotic symptoms, anxiety, and sedation
Zuardi et al. (77) Patients with bipolar disorder (n = 2) CBD oral 600 – 1200 mg/day during 25 days CBD has no effect on symptoms No side effects of CBD reported
Bhattacharyya et al. (43) Healthy volunteers (n = 6) CBD 5 mg i.v. immediately followed by 1.25 mg THC i.v. CBD antagonizes THC-induced psychotic symptoms CBD and THC have opposite effects on regional brain function
Bergamaschi et al. (78) Healthy controls (n = 12) and patients with social phobia (n = 24) CBD oral 600 mg Reduction of anxiety scores in patients, no effect in controls No physical effects or side effects of CBD reported
Crippa et al. (79) Patients with social phobia (n = 10) CBD oral 400 mg No effect on psychological scores No physical effects; SPECT: CBD exerts its effects via limbic and paralimbic areas
Nicholson et al. (80) Healthy volunteers (n = 8) CBD 5 mg + THC 5 mg; CBD 15 mg + THC 15 mg, via mouth spray THC (15 mg) increases drowsiness, antagonized by CBD (15 mg)
Hallak et al. (81) Schizophrenic patients (n = 28) CBD oral 300 and 600 mg acute No positive effects in Stroop Color Word Test No significant side effects of CBD reported
Hallak et al. (82) Healthy volunteers (n = 10) CBD oral 600 mg and ketamine i.v. CBD increases activating effects of ketamine (BPRS); reduction of ketamine-induced depersonalization (CADSS) No effect of CBD on HR and BP

a This concerns experiments with one group of 15 subjects from which the results have been spread over four different publications; BP, blood pressure; BW, body weight; CADSS, Clinician Administered Dissociative States Scale; HR, heart rate; i.v., intravenously; PD, Parkinson disease.

Several studies have shown that cannabis and THC dose-dependently cause cognitive and psychomotor function impairments along with memory, (selective) attention, locomotion, perception, and response impairments (83–85). The effects occur most strongly during the first hour after smoking a joint and between 1 and 2 h after oral intake. Little experimental research exists on the effects of CBD alone or in conjunction with THC on cognitive and psychomotor functions. The studies performed so far show few “protective” effects of CBD on cognitive functions. Morgan and colleagues identified a few such effects on memory functions, but the research on this aspect of CBD has inconsistent findings (45, 49).

Although no human studies have specifically investigated the long-term effects of the combined effect of THC and CBD on cognitive functioning, there are indications that CBD may have some neuroprotective properties. In some neurodegenerative diseases that are often associated with declines in cognitive functioning, such as Alzheimer’s and Parkinson’s diseases, CBD may have some role in treatment or prevention (86–89).

The ratio of THC to CBD may play a role in the risk of addiction (90). Morgan and colleagues examined whether there is a difference in attentional bias between users of cannabis having a relatively high CBD/THC ratio versus cannabis having a low-CBD/THC ratio. Much weaker attentional bias for cannabis-related stimuli was found for users of cannabis with a high CBD content than for users of cannabis with a low-CBD content. Furthermore, the extent to which both groups appreciated the self-selected drug and the strength of the desire for their drug (“wanting”) were investigated. High CBD content led to diminished appreciation and weaker desire for the drug relative to low-CBD content. The researchers concluded that cannabis with a high CBD content confers less risk for developing an addiction than cannabis with a low-CBD content (90). Whether smoking hashish in practice diminishes addiction risk in comparison with smoking highly potent marijuana should be further investigated.


Cannabis is not a safe drug. Depending on how often someone uses, the age of onset, the potency of the cannabis that is used and someone’s individual sensitivity, the recreational use of cannabis may cause permanent psychological disorders. Many recreational users of cannabis will never be faced with serious or permanent health deficits. However, for some users, the use of cannabis may cause undesirable psychological side effects, such as cognitive impairment, anxiety and paranoia, and an increased risk of developing chronic psychosis and addiction. Despite all of the publicity surrounding cannabis, remarkably few studies have been performed that examined the relationship between a possibly harmful effect of THC and a possibly protective effect of CBD. The few studies that exist on the effects of CBD show that this cannabinoid can counteract some of the negative effects of THC, although their results have not always been consistent. The question remains how the findings from laboratory studies, often employing high doses of CBD and high CBD/THC ratios, can be extrapolated to the typical practices of the recreational cannabis user. Few or no adverse effects of CBD have been proffered, and where CBD has been found to have an effect, it is usually in a “positive” (i.e., salubrious) direction. The evidence favoring a beneficial effect of CBD therefore merits further investigation in studies in which the amounts and ratios of CBD and THC correspond to the daily practices of recreational cannabis use.

Conflict of Interest Statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


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I Took CBD Oil Every Day for My Anxiety—Here’s What Went Down

Dana Myers, LCSW is a licensed clinical social worker and life coach based in Philadelphia. She has a special interest in how race, sex, gender, ethnicity, social status and competencies impact those in marginalized communities and aims to help her clients find purpose and peace in life.

Michelle Regalado is a seasoned editor, fact-checker, and content strategist with expertise in women’s lifestyle news.


When I first learned about CBD oil, I’ll admit I was a bit skeptical. My mind immediately turned to weed and the unnerving experiences I’d had with heightened anxiety in college. For me, a person who’s already predisposed to overthinking, marijuana, no matter what the form, would typically put my mind into overdrive and result in a common yet dreaded side effect: Paranoia. But, let’s back up a bit. What even is CBD?

What is CBD?

A bit of online digging led me to realize that the active ingredient in Charlotte’s Web Everyday Plus Hemp Oil, the product I’d been offered to test, was the chemical compound CBD, which stands for cannabidiol. Unlike THC, the other crucial compound in hemp and marijuana plants, CBD (when derived from the hemp plant) does not produce the psychoactive effects that make you feel “high”; instead, emerging science has hinted that CBD may actually ease anxiety, and therefore, makes you less likely to freak out.  

For example, one study comparing the effects of THC and CBD found that, while THC increased anxiety by activating the neurotransmitters involved in the “fight or flight” response, CBD actually repressed autonomic arousal—or the nervous system response associated with sudden increases in heart rate or respiration.   In other words, CBD may be ideal for people looking to relax and unwind.

While the science behind CBD’s effectiveness for treating anxiety, pain, and insomnia is still in its infancy,   Charlotte Figi’s inspiring story sounds promising. Figi, a 6-year-old girl diagnosed with a rare and resistant form of epilepsy known as Dravet syndrome, was placed on hospice care and given a “do not resuscitate” order when her parents, desperate and frustrated with pharmaceutical medication, considered medical marijuana; specifically, a strain low in THC and high in CBD. Charlotte is now nearly seizure-free since she began supplementing with Charlotte Web’s CBD oil, which the brand named after Figi.

Legal and Safety Things To Know About CBD

The current CBD industry is like the internet’s early years. the Wild West. Legally, speaking, a Harvard Medical School blog post reads, “All 50 states have laws legalizing CBD with varying degrees of restriction, and while the federal government still considers CBD in the same class as marijuana, it doesn’t habitually enforce against it.”   With heightened interest around CBD, it’s important to note that because CBD is currently unregulated, it’s difficult to know what you’re getting (whether that’s a tincture—commonly referred to as CBD oil, which is often combined with a carrier oil like coconut oil—topical products like creams and balms, sprays, or capsules), despite product labels and brand promises, the blog post further reads. It’s also important to note that people experience CBD differently. For the most part, the National Institute of Medicine says that while most people can tolerate CBD, side effects do exist. They might include dry mouth, drowsiness, and reduced appetite, among others.  

That said, those interested in exploring the potential benefits of CBD should consult with their doctor (especially if you are pregnant, nursing, or currently taking medication) and be mindful of your dosage, writes Consumer Reports. And before you buy, Megan Villa, co-founder of the hemp-focused website and shop Svn Space, told Shape magazine to seek out a certificate of analysis. “Ask for a COA for the batch number of the product you have, since these products are made in batches,” she said. “You need to match the batch number to the COA that pertains to it.” Then, scan the report for potency (i.e. does the number of milligrams of CBD that the product label touts match the lab report?), contaminants and pesticides, and mold (which should live under the “Microbiological Testing” part of the report). Go a step further and note whether the testing lab is GMP (Good Manufacturing Principles) certified, and whether the lab is registered with the Food and Drug Administration (FDA). Shape magazine also suggests purchasing CBD products made from domestically-grown hemp, and reading up on the difference between full- and broad-spectrum and CBD isolate.

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With that, I threw caution to the wind and asked for a sample. Here’s what happened—including what it feels like—when I took one full dropper of Charlotte’s Web’s Everyday Plus Hemp Oil in the mint chocolate flavor every morning for seven days.

My First Impression

It was actually a bad bout of jet lag after a trip to California that inspired me to finally test out the CBD oil (I’ll admit that my weed-based reservations kept me from trying it for the first few months). Knowing that the oil had also helped people with sleep issues, I squeezed one full dropper of the Everyday Plus oil onto my tongue, per the instructions, and waited.

Thirty minutes later, I was surprised by how subtle the effect was. While I expected a hazy nodding-off effect similar to melatonin’s, the oil simply relaxed my body ever so slightly—my heart stopped pounding against my chest, my legs stopped kicking beneath my sheets, my mind stopped racing. I wasn’t sure if it was the oil or the late hour, but eventually, physical relaxation gave way to mental relaxation, and I drifted off to sleep.

Reflecting the next morning, I was most surprised by the fact that I never felt “high” in any way—there was never a moment of It’s kicking in; I can feel it now like with pain medications or even anti-anxiety drugs. Considering it takes time, consistency, and the right dosage to experience the full effect, I continued taking the oil once a day for the next six days. Here’s what went down.

It Made Me Less Anxious and Edgy

Rather than overthinking a sternly worded email or analyzing a social interaction, I found it easier to recognize the irrationality of these thoughts and actually let them go.

While normally I’d be slightly tripped up by little things like an overly crowded subway car or a full inbox at work, the CBD oil seems to have taken the edge off of my anxiety a bit. Rather than overthinking a sternly worded email or analyzing a social interaction, I found it easier to recognize the irrationality of these thoughts and actually let them go. In some ways, I feel more like myself. With that said, I’ve still experienced some social anxiety when meeting new groups of people—I’d be interested to see what taking the full recommended dose would do.

I’m More Focused At Work

I work well under pressure, but being extremely busy at work has almost made me less productive—I’m constantly distracted by email, Slack, and the people around me, to the point where getting my work done becomes difficult. This week, however, I’ve found it easier to put my blinders on, block out all distractions (especially social distractions), and focus on one task at a time. I think this is partly related to the lessened anxiety—I feel more frazzled and off task when my anxiety is running high. It almost feels like a newfound sense of clarity and calm that enables me to focus.

I’m Falling Asleep Faster

I assume this is also a side effect of feeling less anxious, but I seem to fall asleep faster; within the 20-30-minute range rather than my normal 45 minutes to one hour (or longer). Not only do I seem to be skipping or at least shortening the whole tossing-and-turning phase of my sleep cycle, but I’m able to snap out of the overthinking that often keeps me up at night. Of course, there’s no telling whether a big life event would disrupt this newfound bliss, but I’d like to think it’s helped on a day-to-day basis.

My Experience With CBD

Would I say that CBD oil has fundamentally changed my life? No. But per the Charlotte’s Web website, this is the typical first experience. “Anyone who has ever started a new vitamin or supplement routine knows the short answer to how long it takes to kick in is—’it depends.’ For many newcomers, they’re not sure what to imagine, or some anticipate a huge change right away. For most of us, though, dietary supplements take time.”

With that said, I’m definitely intrigued enough by the subtle effects to continue taking the oil and to possibly up the dosage to the recommended two full droppers of the 30mL bottle per day. Plus, I take comfort in knowing that it’s an all-natural product that’s responsibly grown on family farms in Colorado. Something that’s safe, legal, requires no prescription, and makes me less anxious, less scatterbrained, and more focused? I’m definitely on board.

Explore the World of CBD

Looking to learn more about CBD? These are some of my favorite products to help get you started.

For those new to CBD, Charlotte’s Web recommends this hemp oil. Containing 17mg of CBD per 1mL serving, this CBD oil is also U.S. Hemp Authority Certified. Choose from four different flavors including Lemon Twist, Mint Chocolate, Orange Blossom, and Olive Oil.

Go deep on the subject of CBD with this book that includes case studies, interviews with doctors, an overview of the latest cannabis research, and how scientists are exploring cannabis for various medical uses. There is also an explainer about the difference between CBD products made from industrial hemp versus in a lab, and products made from the whole marijuana plant.

Charlotte’s Web inaugural CBD oil product comes in two flavors; Olive Oil and Mint Chocolate. It’s also its most potent. According to its website, its Original Formula Hemp Extract Oil comes with 50mg CBD per mL.

Gretchen Lidicker puts a lifestyle spin on the world of CBD as the author draws on the “knowledge of leaders in the health and wellness world” to explain why CBD has become a top beauty and wellness trend for top athletes and celebrities. The book also includes recipes and recommendations for how to choose a top-quality CBD product.

This travel-friendly roll-on is packed with CBD and fragrant essential oils, including lavender, bergamot, and chamomile, for an easy de-stress quick fix. The result? “That elusive feeling of wakeful calm,” reads the Sagely Naturals website.

With this book, CBD is explained from A to Z and breaks down the good, bad, and ugly of a fledgling industry that is poised for rapid growth. CBD: 101 Things You Need to Know About CBD Oil covers what it is, why people take it, who it’s for (and who it isn’t for), its myriad forms, and more.

Lord Jones’ High CBD Formula Body Oil combines CBD with organic avocado, jojoba and safflower oils for smooth, hydrated skin. Each bottle has 100mg of CBD.

Charlotte’s Web’s Extra Strength Capsules feature 25 mg of CBD per capsule. The website offers capsules as a convenient and precise way to take CBD—on the go, stash them in your gym bag, pocket, etc.

Byrdie takes every opportunity to use high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial guidelines to learn more about how we keep our content accurate, reliable and trustworthy.

Blessing EM, Steenkamp MM, Manzanares J, Marmar CR. Cannabidiol as a potential treatment for anxiety disorders. Neurotherapeutics. 2015;12(4):825-836. doi:10.1007/s13311-015-0387-1

Shannon S, Lewis N, Lee H, Hughes S. Cannabidiol in anxiety and sleep: A large case series. Perm J. 2019;23:18-041. doi:10.7812/TPP/18-041

Charlotte’s Web CBD Oil Review

Commissions we earn from partner links on this page do not affect our opinions or evaluations. Our editorial content is based on thorough research and guidance from the Forbes Health Advisory Board.

Table of Contents

  • Charlotte’s Web CBD Oil at a Glance
  • About Charlotte’s Web
  • Cost
  • Potency
  • Quality
  • The Charlotte’s Web Experience
  • Final Thoughts

You’ve probably noticed the selection of cannabidiol (CBD) products lining the shelves of many grocery, pharmacy or health food stores. Maybe you’ve experimented with a couple brands yourself, hoping it might prove a good addition to your health routine. If so, you’re not alone. Cannabidiol (CBD) is increasingly popular and often used by people looking to boost their overall wellness.

“The three most common reasons people use CBD are for sleep, mental health and pain relief,” says Lea Durante, a nurse practitioner and owner of Lea Durante Consulting, a wellness and CBD consulting company in Napa, California. “CBD is an amazing tool for improving mental and physical health, but guidance and support are essential for optimum benefits.”

Penguin CBD Oil

On Penguin’s Website

$45 per container

Penguin CBD Gummies

On Penguin’s Website

$45 per container

Penguin CBD Cream

On Penguin’s Website

$55 per container

Penguin CBD Capsules

On Penguin’s Website

$45 per container

(Note: All prices are accurate as of publication and are subject to change.)

I wanted to find out whether CBD oil might be right for me, so I purchased a 30-milliliter bottle of Charlotte’s Web CBD oil containing 60 milligrams of CBD per milliliter. I consumed it twice a day over a period of three weeks. Here’s a review of my experience.

Charlotte’s Web CBD Oil at a Glance


  • Cost: At $120 for a 30-milliliter bottle of CBD oil with 60 milligrams of CBD per milliliter, Charlotte’s Web CBD Oil is more expensive than other CBD oils on the market.
  • Potency: One dose of .5 milliliters, which is clearly marked on the dropper, contains 30 milligrams of CBD. A 60-milligram dose requires one full dropper of CBD oil.
  • Quality: This product meets high standards for label accuracy and transparency of ingredients, levels of THC and presence of heavy metals, solvents, pesticides, yeasts and molds.

What I liked:

  • Certificate of analysis (COA) for all products available on company website
  • Dropper dose clearly marked
  • This CBD product is Certified Organic.

What I didn’t like:

  • High price, making the product expensive to use daily

About Charlotte’s Web

Charlotte’s Web Stanley Brothers, founded in 2011 and headquartered in Boulder, Colorado, creates full-spectrum (total plant) hemp health supplements. Its CBD products include oils, gummies, capsules and topicals like gels, creams, balms and sprays.

Charlotte’s Web grows all of its hemp plants on family farms in Colorado, Oregon and Kentucky. However, not all Charlotte’s Web CBD products are Certified Organic. All Charlotte’s Web products are gluten-free, vegan and non-GMO. Each batch is analyzed by a third-party laboratory for the product’s certificate of analysis (COA). The COA shows the quantity of CBD and cannabinoids present in the product, as well as levels of heavy metals, pesticides, solvents and THC found in each batch.

Charlotte’s Web has a Better Business Bureau (BBB) rating of “F.” According to the BBB, the “F” rating results from 17 customer complaints about Charlotte’s Web products not arriving as promised, nonresponsive customer service and the company’s failure to respond to BBB inquiries regarding customer complaints.

I purchased the 30-milliliter bottle of Charlotte’s Web CBD oil tincture, which retails for $120. This size contains 1,800 milligrams of CBD, or 30 milligrams per 0.5-milliliter serving, a cost of $2 per serving. That price is higher than many other brands of CBD oil, but subscribers who sign up for regular shipments can receive a 20% discount on the full price.

The Certificate of Analysis (COA) for this product shows it to be a high-quality CBD oil overall, and some people may not mind paying the higher-than-average price. Charlotte’s Web also offers a starter size of this product—a 10-milliliter bottle for $50.


The bottle of Charlotte’s Web CBD oil I purchased contains a total of 1,800 milligrams of CBD. I started with the recommended single-serving dose of .5 milliliters containing 30 milligrams of CBD two times a day. After a couple of days, I increased my dose to 60 milligrams twice daily—I felt comfortable taking a higher dose because I have used CBD oil products before. However, someone new to CBD may want to start with a smaller dose and gradually increase it once they’re familiar with how their body reacts to the product.


The product I chose is labeled USDA Certified Organic. The Certified Organic designation ensures that the soil, water, growing and manufacturing conditions are clean and free of contamination from pesticides, herbicides, heavy metals, fungus and bacteria.

“Hemp is a bio-accumulator, absorbing the environmental conditions it’s grown in, which then become concentrated in the final product,” says Durante, making this organic certification all the more important.

This product’s certificate of analysis (COA)—easily available on the website’s COA lookup page under the tag “Certificate of Analysis”—shows the amount of CBD in one millilter (69 milligrams) slightly exceeds the 60 milligrams listed on the product label.

Charlotte’s Web CBD oil is available in three flavors: orange blossom, mint chocolate and lemon twist. I chose orange blossom, which didn’t taste much like oranges, but it wasn’t unpleasant, either.

Pure, Premium, Powerful CBD

FAB CBD’s products are made from organically grown, lab tested, Colorado hemp. Their range of products include CBD oils, gummies, topical CBD cream, dog treats and more.

The Charlotte’s Web Experience

Since I’ve tried CBD oil before as a sleep aid and to reduce stress, I chose a product with a higher potency (60 milligrams per milliliter) than someone with no CBD experience might use. During the first few days, I didn’t feel much of an effect on my mood or stress level with a 30-milligram twice-daily dose, so I upped my consumption to 60 milligrams twice a day.

With the higher dose, I thought I might feel more relaxed and focused; instead, I felt drowsy and slightly irritable. Drowsiness and irritability are both signs that the dose may be too high, so I reduced my consumption back to the 30-milligram dose twice a day. When taking the lower dose, I was a little more relaxed and focused for a few hours after taking the tincture.

After researching CBD, I learned that guessing a dosage that “might” work was a classic beginner’s mistake. It usually takes two to four weeks of using CBD with expert guidance to get a good idea of its effects. Each person’s natural endocannabinoid system (which interacts with CBD) is different and there isn’t a one-size-fits-all CBD dose and dosage regimen.

“Everyone’s endocannabinoid system truly is as unique as their fingerprints, so the use of CBD needs to be personalized,” says Durante. “Working with a peer or coach or clinical professional that has experience with CBD is vital to getting results. I encourage each person I work with to be actively engaged in the process of starting low, going slow and taking CBD consistently to find that ‘sweet spot.’”

Final Thoughts

Overall, the 30-milligram dose of Charlotte’s Web CBD Oil helped me feel calmer and less stressed throughout the day. However, the $120+ price tag for a month’s supply was more than I could easily afford if I were to add this product to my long-term daily wellness regimen.

Before choosing this product, I recommend comparing prices and reviewing COAs of other CBD oils that meet similar USDA Certified Organic, labeling and transparency standards. For best results, consult an integrative medicine physician, naturopathic clinician or holistic practitioner who is knowledgeable about CBD oil and can guide your dosage regimen safely and effectively.