CBD Vs THC: Two Cannabinoids with Very Different Effects

There are hundreds of known cannabinoids in a cannabis plant; some estimates place the number around 400. The most well documented are cannabidiol (CBD) and tetrahydrocannabidiol (THC). Anyone seriously considering cannabis use should know the difference between CBD and THC. Even some long-term users don’t know the difference or only have a rudimentary understanding. If you fall into either of these categories, then you arrived to the right place. This CBD versus THC primer explains everything in a layman-friendly manner.

CBD Versus THC: The General Understanding

If you ask most cannabis users what the difference is between CBD and THC, you’ll likely get a response like the following: THC gets you high and CBD does not.

This response is accurate, but very generalized. The difference goes far deeper once you examine these phytocannabinoids at the molecular level. Studies reveal that the two have overlapping benefits as well as different side effects. The legality regarding the CBD and THC also differ depending on state of residence.

Let’s examine the two separately before circling back and comparing the two back-to-back.

What Is CBD?

CBD is the non-psychoactive compound available primarily in hemp. See our section on “What Is Hemp?” for a detailed explanation. Most CBD oils are derived from industrial hemp, which consists of the fibrous portions of the cannabis species: cannabis sativa. Industrial hemp is often the go-to source for CBD oils and tinctures since it contains high CBD concentrations and little THC. Various dispensaries have committed to various crossbreeding cultivations to produce a hemp yield with just the right CBD to THC ratio.

Benefits of CBD

CBD has various science-backed benefits. Let’s have a look at some of the medicinal properties.

  • CBD treats inflammation and pain – source1
  • CBD treats somnolence (excessive drowsiness) – source2
  • CBD treats seizures – source3
  • CBD treats anxiety – source4
  • CBD treats depression – source5
  • CBD lowers risk of heart disease – source6

Aside from the countless studies and clinical trials, there are also dozens upon dozens of anecdotal evidences from users across the world. This also includes various reports from parents who treated their children and even pet owners that treated their canine with CBD.

CBD Effects on the Cannabinoid System

CBD exerts an influence on the endocannabinoid system (ECS) and more specifically, the CB1 and CB2 receptors. Unlike other cannabinoids, CBD does not bind directly to the CB receptors. Instead, it inhibits certain metabolic enzymes from breaking down the body’s natural endocannabinoids. In other words, CBD increases the body’s natural output of endocannabinoids.

As you will later see, this manner of influence on the ECS system differs from how THC interacts with the CB receptors.

Legal Status of CBD

This is where readers have to perform some supplemental research of their own. When it comes to hemp-derived CBD, the products are legal to buy, sell and use in all 50 states. The keyword here, though, is “hemp-derived.” As we mentioned earlier, hemp is the fibrous portion of the plant with minute to no traces of THC. Hemp oil and hemp-derived CBD oil have been legal in all states since 2014, thanks to the passage of the Farm Bill. The bill defines industrial hemp and legal CBD differently from the Drug Enforcement Association’s definition. Long story short, if you’re a user, you can use hemp CBD in any form, including consumption via edibles, vaping, etc.

There is also another variety, which is marijuana-derived CBD, and this is a whole different issue altogether. Marijuana-derived CBD is cultivated from the flower and buds of cannabis and contains higher THC traces.

We can’t tell you the precise legality of marijuana-based CBD because it depends on your state of residency. In some states, marijuana-derived CBD remains outlawed. In others, it’s permitted for medicinal use with a doctor’s prescription, while others allow recreational use. Even in states where medical use is permitted, prescription may be limited to certain diagnoses, and this differs by region.

See Americans for Safe Access for a breakdown of CBD laws by individual state.

What Is THC?

As most of you may know, this cannabinoid is responsible for the high and creating altered states of consciousness, hence why it’s favored among recreational 420-friendly folks.

THC is found in far greater concentrations in the female cannabis plant. The hemp plant, just so you know, is the male. While the word “marijuana” is used as a general term for cannabis by non-users, users and industry insiders use the term to specifically describe the female plant.

Cannabis plants, by the way, can also be hermaphrodite and have both male and female organs!

THC concentrations specifically come from the flowers and their buds, which are known as “colas.” The THC is contained within the colas’ trichomes, which appear as crystal-like splotches.

Benefits of THC

Some of the benefits of THC overlap those of CBD. Let’s look at some of these medicinal qualities.

  • THC Treats Pain – source7
  • The THC-infused drug Dronabinol alleviates nausea – source8
  • THC reduces the time it takes to fall asleep – source
  • Contrary to popular belief, THC does not harm the lungs regardless of whether it’s ingested or vaped. In fact, it might enhance lung capacity – source
  • THC has anti-cancer properties and may slow the growth of brain tumor cells – source
  • THC in low doses relieves anxiety. Higher doses, though, may have the opposite effect – source

THC Effects on the Endocannabinoid System

Unlike CBD, THC has a more direct effect on the ECS. THC mimics the behavior of the body’s natural endocannabinoids and binds mainly with the CB1 receptors located primarily in the brain. To be more precise, THC acts as a presynaptic cell. Instead of traveling via synapse from a neuron to a receptor site like a regular neurotransmitter, it travels in the reverse direction and binds to cannabinoid receptors.

By binding to CB receptors, it may delay the release of neurotransmitters that control our mood and states of mind. This accounts for the psychoactive high. THC occupying the CB receptors also limits the ability of natural endocannabinoids to do the same. While this results in various benefits like the ones described earlier, it can also have a host of side effects, especially among first-time users.

The delayed release of neurotransmitters may translate to slower reaction time to external stimuli. It may, for instance, slow your reaction time when driving, playing a sport or taking a test.

Legal Status of THC

Any cannabis product containing over 0.3 percent THC is considered a controlled substance and is illegal under the Controlled Substances Act. THC is treated as a controlled substance, much like heroin and cocaine. It is classified under federal law as a Schedule I drug. This means it is highly addictive while providing little to no medicinal value, even though we just presented studies that claim otherwise.

While THC is illegal under federal provisions, a bill called the Rohrabacher-Farr Act was signed into law in 2014. It essentially states that the DEA cannot interfere in matters regarding cannabis laws at the state level. For this reason, you have to refer to the laws governing your respective state of residence.

When discussing CBD legality earlier, we brought up the difference between hemp-derived CBD and marijuana-derived CBD. The laws regarding the latter essentially pertain to THC since the marijuana plant contains far higher concentrations of the psychoactive compound.

State laws differ drastically. Even in states where medical and/or recreational use is permitted, there may be specific laws regarding the amount you can possess. For growers, there are additional measures regarding the number of plants you can keep in the home or transport from one location to another.

CBD Versus THC: Side-By-Side Comparison

Let’s review CBD and THC, so you can see how they are similar and the areas where they differ.


  • CBD comes from industrial hemp, which is the male cannabis plant.
  • THC comes from the marijuana female cannabis. The extract is mainly acquired from the plant’s colas, or cluster of flowers and buds.


CBD and THC have some overlapping benefits. Separate studies show, for example, that both may suppress pro-inflammatory cytokines and reduce pain. Both also aid in various sleep disorders.

Effects on the Endocannabinoid System

  • CBD does not bind directly with CB receptors. Instead, it enhances natural endocannabinoid availability by inhibiting certain metabolic enzymes.
  • THC acts as a presynaptic cell and binds directly with CB1 and some CB2 receptors, mimicking the action of natural endocannabinoids.

Side Effects

  • We didn’t discuss the side effects of CBD because they are rare, minor and dissipates within days. Some users may experience sensations like dry mouth, slight nausea and mild diarrhea. CBD is non-addictive.
  • You need to be far more careful with dosage regarding THC. Side effects include the same as CBD; some users may also experience anxiety, the jitters or depression. This is especially true if you’re prone to mood imbalance. Unlike CBD, research suggests users can become physically addicted to THC and develop withdraw symptoms.

Legal Status

  • Hemp-derived CBD is legal to buy, sell, and use as long as THC content remains below 0.3 percent.
  • State laws differ regarding marijuana with THC. States outlaw it altogether, permit medical use with prescription only, or allow medical and recreational use.

CBD Versus THC: Know the Difference Before Your First Cannabis Use

Most CBD products available in health stores and e-stores come from hemp. This is the case with our personal CBD supplier recommendations at our “Where to Buy” page. If you choose to experiment with THC, then you have to look up your state law. If your state permits recreational use, then you can acquire THC products at local dispensaries.

Medical References

Russo E. Cannabinoids in the management of difficult to treat pain. Ther Clin Risk Manag. 2008;4(1):245-259. [PMC]
Murillo-Rodríguez E, Millán-Aldaco D, Palomero-Rivero M, Mechoulam R, Drucker-Colín R. Cannabidiol, a constituent of Cannabis sativa, modulates sleep in rats. FEBS Lett. 2006;580(18):4337-4345. [PubMed]
Perucca E. Cannabinoids in the Treatment of Epilepsy: Hard Evidence at Last? J Epilepsy Res. 2017;7(2):61-76. [PMC]
Blessing E, Steenkamp M, Manzanares J, Marmar C. Cannabidiol as a Potential Treatment for Anxiety Disorders. Neurotherapeutics. 2015;12(4):825-836. [PMC]
de M, de O, Coutinho D, et al. Antidepressant-like and anxiolytic-like effects of cannabidiol: a chemical compound of Cannabis sativa. CNS Neurol Disord Drug Targets. 2014;13(6):953-960. [PubMed]
Stanley C, Hind W, O’Sullivan S. Is the cardiovascular system a therapeutic target for cannabidiol? Br J Clin Pharmacol. 2013;75(2):313-322. [PubMed]
Greenwell G. Medical marijuana use for chronic pain: risks and benefits. J Pain Palliat Care Pharmacother. 2012;26(1):68-69. [PubMed]
Abrahamov A, Abrahamov A, Mechoulam R. An efficient new cannabinoid antiemetic in pediatric oncology. Life Sci. 1995;56(23-24):2097-2102. [PubMed]

CBD Oil Effects: Cannabidiol’s Influence on the Endocannabinoid System

The benefits of cannabidiol oil are well documented. Medicinal uses are far-reaching, and scientific studies have proven cannabidiol to be effective for pain relief, insomnia, anxiety, seizures and much more. How does CBD achieve these effects at the anatomical level? Let’s examine CBD oil effects and the mechanisms that result in the sought-after reliefs.

A Lesson in the Endocannabinoid System

To understand CBD oil effects on the body, you need to understand how the human anatomy works. It all comes down to the endocannabinoid system (ECS). The ECS is not unique to humans; it’s found in virtually all vertebrate species.

The ECS is located throughout the body and not concentrated in a single area. It consists of these three major components:

  • Cannabinoid receptors
  • Endocannabinoids
  • Metabolic enzymes

Cannabinoid Receptors

Cannabinoid receptors are located on cell surfaces and detect changing conditions taking place outside of the cell. It transmits information to the cell, and the cell responds and adapts accordingly. The two primary receptors include CB1 and CB2.

CB1 resides mostly in the brain and nervous system. When you ingest or vape THC, the psychoactive cannabinoid binds with CB1 receptors, leading to the high and stoned sensation.

CB2 resides mostly in the immune system, including immune cells and macrophages. This receptor mainly regulates pain and inflammation.


Endocannabinoids, also known as endogenous cannabinoids, are molecules that bind to CB1 and CB2. The body produces endocannabinoids naturally and on demand as needed.

Various types of endocannabinoids exist. One of the more researched forms is a molecule called anandamide, which facilitates pain reduction, healthy sleep cycles, anxiety relief and more. Some people have referred to anandamide as the “bliss molecule” due to its antidepressant-like effects.

Endocannabinoids are retrograde signalers.  Most neurotransmitters only travel in one direction, from a presynaptic cell to a postsynaptic cell. Endocannabinoids direct information from the post- to the presynaptic cell. The signaling informs the latter to produce more or less of certain chemicals and hormones.

Metabolic Enzymes

These enzymes metabolize endocannabinoids right after they’re used and no longer needed. Unlike hormones and neurotransmitters, endocannabinoids are never stored and reserved for later use.

These three ECS components regulate everyday bodily functions, such as our circadian rhythm, appetite, mood, memory, pain, and pleasure/reward system.

How Do Cannabinoids Fit In?

Researchers are just beginning to understand the complex role of cannabinoids on the endocannabinoid system1. To keep the explanation simple, cannabinoids mimic the behavior of endocannabinoids and bind to cannabinoid receptors in a similar fashion. Cannabinoids derived from cannabis are known as phytocannabinoids, though they’re typically referred to as cannabinoids.

As it turns out, thendocannabinoid system recognizes and responds to phytocannabinoids the same way as internally-produced endocannabinoids.

Phytocannabinoids Versus Endocannabinoids

Despite having near-identical influences on the ECS, phyto- and endocannabinoids2 do have some differences. One may wonder, for example, why it is that humans don’t get high naturally from endocannabinoids. It comes down to the metabolic enzymes, which do not break down THC the way it does with endocannabinoids. This allows THC to remain in the body for prolonged periods and exert psychoactive influences.

Unlike endocannabinoids, which only interact with CB receptors, phytocannabinoids may also interact with other receptor types, neurons and neurotransmitters.

Effects of CBD on the Endocannabinoid System

CBD interacts with the endocannabinoid system in a different way than THC and other cannabinoids. For starters, it does not bind to CB1 and CB2 receptors. The effects on the cannabinoid receptors are more indirect. One way it does this is by stopping the metabolic enzymes from breaking down the body’s natural supply of endocannabinoids.

Studies3 show that CBD inhibits the fatty acid amide hydrolase, a type of metabolic enzyme that causes anandamide inactivation.  In other words, CBD increases availability of endogenous cannabinoids. This is why CBD does not produce the high you get from THC; there is no direct interaction between cannabidiol and cannabinoid receptors. The benefits of pain relief and relaxation is from the greater bioavailability of anandamide and other endocannabinoids.

CBD Oil Effects on Non-Cannabinoid Receptors

As mentioned, one way phytocannabinoids differ from endocannabinoids is the ability to interact with other receptors. Cannabis is a pleiotropic substance, meaning it affects the ECS via multiple molecular pathways.

CBD, in particular, has been shown in studies to interact with opioid receptors in the brain. This explains the medical research4 supporting CBD use for managing opiate withdrawal.

Another study5 reveals an interaction between CBD and vanilloid (TRPV1) receptors. This receptor acts as an ion channel and mediates pain, inflammation, and body temperatures. TRPV1 also mediates the effects of various medicinal herbs.

Some people also take CBD for cancer management. This is because CBD also binds with peroxisome proliferator activated receptors (PPARs). Studies6 show that CBD activates these receptors and induces tumor regression in the lungs.

These are just some of the non-cannabinoid receptors CBD has some level of influence on. Some estimates indicate that CBD interacts with as much as 65 types of receptors. You can see now why the effects of CBD are far-reaching and why hemp as medicine is gaining traction.

Does Taking Phytocannabinoids Inhibit Endocannabinoid Production?

Some folks have expressed concerns that taking too much CBD from an external source may suppress the body’s natural ability to produce endocannabinoids. Taking anabolic steroids or TRT, for example, certainly hurts the body’s ability to produce testosterone naturally. Is it the same when taking CBD oil?

There are no studies that suggest this may be a possibility. CBD doesn’t even bind directly to CB receptors. Remember, as we mentioned, CBD actually elevates certain endocannabinoids by inhibiting metabolic enzymes.

What Causes the Calm-Inducing Effects of CBD?

Most people who take CBD oil report a feeling of ease and the ability to forget about their problems for the moment. What attributes to this feeling of immense relaxation?

One other non-cannabinoid receptor is the 5-HT1A receptor, which according to studies7, regulates serotonin, or the “feel-good” hormone.

Aside from regulating serotonin, the 5-HT1A receptor has also been linked to other biological and neurological responses, such as anxiety, sleep, appetite and pain perception. This explains why CBD use also helps improve deficiencies in these areas. The 5-HT1A can actually produce both an excitatory and inhibitory response, depending on the triggering chemical or molecule.

CBD has an inhibitory response on 5-HT1A. This inhibits the receptor’s ability to signal the slow-down of serotonin production, thus leading to more output of the calming hormone.

What About THC and Anxiety?

CBD, for the most part, does not induce anxiety. Unfortunately, the same cannot be said of CBD products with THC. Some people have reported feelings of extreme paranoia, disorientation and inability to complete even the simplest of tasks, such as walking straight or sending a text. These sensations are not uncommon among first-time users who try a friend’s THC-laced Rice Krispies Treat or other edibles.

Why does this happen with THC, but not CBD? What is taking place at the ECS level? Remember that unlike CBD, THC actually binds to the CB1 and CB2 receptors. This causes a surge of neurotransmitter releases, including serotonin, dopamine and GABA. GABA is especially relevant in this instance; this neurotransmitter inhibits the firing of certain neurons, including the neurotransmitter norepinephrine. Norepinephrine induces alertness; in excess, it can also cause anxiety. GABA, therefore, induces relaxation by suppressing norepinephrine.

In some people, suppressed norepinephrine can cause a rebound effect. This leads to an overstimulation of the brainstem’s limbic forebrain, which regulates arousal and overexcitement. In turn, this leads to excess cortisol release, causing stress and anxiety. While not everyone who ingests THC experiences this phenomenon, those who do say they don’t ever want to go through that again. The lesson here is to stick with CBD-only products from reputable suppliers.

To avoid a bad experience, only buy from licensed suppliers. Our Where to Buy section contains a listing of reliable CBD manufacturers.

CBD Effects on Epilepsy

One other notable use of CBD is reducing the frequency and severity of epileptic seizures. Researchers are exploring CBD as a viable alternative; roughly one-third of epilepsy patients do not respond to traditional anticonvulsants. This is where CBD for seizures comes in as a viable alternative.

CBD also interacts with glutamate receptor agonists, sodium ion channels and GATA-binding factors (GATA2) in the brain. These are the same systems that traditional anticonvulsants target by binding themselves to these neurons and altering the ion flow. Epileptic seizures are triggered by abnormal electrical activity, which is believed — at least to some degree — to originate from the ion flow between ion channels, glutamate receptors and GATA2.

CBD Effects Are Complex and Warrant Further Studies

The studies of CBD oil on the human anatomy are still limited. There are still interactions with the ECS system that we haven’t even yet begin to understand. What we do know so far, though, is that CBD appears to have a positive effect based on scientific studies and anecdotal experiences from thousands of sworn users.


Medical References

PACHER P, BÁTKAI S, KUNOS G. The Endocannabinoid System as an Emerging Target of Pharmacotherapy. Pharmacol Rev. 2006;58(3):389-462. [PMC]
Fisar Z. Phytocannabinoids and endocannabinoids. Curr Drug Abuse Rev. 2009;2(1):51-75. [PubMed]
Bisogno T, Hanuš L, De P, et al. Molecular targets for cannabidiol and its synthetic analogues: effect on vanilloid VR1 receptors and on the cellular uptake and enzymatic hydrolysis of anandamide. Br J Pharmacol. 2001;134(4):845-852. [PMC]
Ren Y, Whittard J, Higuera-Matas A, Morris C, Hurd Y. Cannabidiol, a nonpsychotropic component of cannabis, inhibits cue-induced heroin-seeking and normalizes discrete mesolimbic neuronal disturbances. J Neurosci. 2009;29(47):14764-14769. [PMC]
Costa B, Giagnoni G, Franke C, Trovato A, Colleoni M. Vanilloid TRPV1 receptor mediates the antihyperalgesic effect of the nonpsychoactive cannabinoid, cannabidiol, in a rat model of acute inflammation. Br J Pharmacol. 2001;143(2):247-250. [PMC]
Ramer R, Heinemann K, Merkord J, et al. COX-2 and PPAR-γ confer cannabidiol-induced apoptosis of human lung cancer cells. Mol Cancer Ther. 2013;12(1):69-82. [PubMed]
Resstel L, Tavares R, Lisboa S, Joca S, Corrêa F, Guimarães F. 5-HT1A receptors are involved in the cannabidiol-induced attenuation of behavioural and cardiovascular responses to acute restraint stress in rats. Br J Pharmacol. 2009;156(1):181-188. [PMC]

CBD Oil Side Effects (Are There Any?)

The benefits of CBD are well documented. We did an entire piece on the medicinal qualities of hemp with the clinical trials to back the claims. Still… can too much of a good thing be bad for you? Too much vitamin C, for example, is known to cause upset stomach and skin flushing. Can CBD – for all of its benefits – cause adverse reactions? We’ll explore some of the potential CBD oil extract side effects and whether users should be concerned or exercise precautionary measures.

CBD Oil Is Generally Safe

Before discussing some of the side effects of using CBD, we want to emphasize that CBD, by and large, is mostly safe. A review of clinical data1 found CBD to have a “favorable safety profile.”

The data reviewed patients who consumed CBD for treating epilepsy and other psychotic disorders. While some subjects did experience side effects, they were mild in comparison to traditional pharmaceutical drugs for treating said medical conditions.

In another study2, patients given doses up to 600 mg of CBD experienced no adverse effects. We should note, though, that doses were administered orally, which has a lower bioavailability compared to vaping or other delivery methods.So, with that in mind, we won’t assume vaping 600 mg of CBD is just as safe.

Side Effects of CBD Oil

CBD oil is not 100% side-effect-free. Some people have more sensitive CB receptors and may respond with unpleasant symptoms. In most cases, the adverse reaction dissipates once the body adjusts.

The aforementioned review of clinical data did find that patients experienced mild symptoms associated with CBD use. This includes:

  • Dry mouth
  • Diarrhea
  • Nausea
  • Vomiting
  • Changes in Appetite (usually an increase)

CBD Interactions with Drugs

are there drug interaction and cbd oil side effects - assorted pills on wooden background
Assorted prescription pills

Does mixing CBD with pharmaceuticals result in unwanted side effects? If you’re on medication, inform your doctor if you’re going to begin CBD supplementation.

CBD use can interfere with your body’s ability to metabolize medicine. This may slow down the breakdown of the drug, causing it to remain in your system longer than necessary. Studies3 show, for example, that CBD use may actually increase the effectiveness of blood thinners. While this may sound like a good thing, the amplified effects may cause complications if you don’t adjust your dose accordingly.

Why does this occur? When taken orally, CBD is metabolized by a liver enzyme known as P450-complex. The same enzyme also metabolizes most pharmaceutical drugs. If the enzyme is busy metabolizing CBD, then it has to delay the metabolization of the medication.

CBD may interfere with any medication that is processed by the liver. There are too many to list, but some examples include:

  • Benzodiazepines
  • Anabolic steroids
  • Fentanyl
  • Antihistamines
  • Macrolide antibiotics
  • Calcium channel blockers

Any CBD oil side effects you experience may not necessarily be from the CBD itself but from the increased potency of the medication due to the delayed metabolization.

CBD Side Effects from Vaping

Vaping CBD may carry its own set of side effects independent of what you might experience from oral CBD. The side effects here stem from the additional additives and not necessarily from the CBD. CBD vape oils and e-liquids commonly contain propylene glycol (PG) as a thinning agent.

The heating coil of lower-quality vape pens produces excess heat, which may convert the PG into tiny polymers that could cause lung irritation.

A study published in the International Journal of Environmental Research and Public Health found that airborne PG can induce asthma and exacerbate allergy conditions. Side effects include watery eyes, wheezing, coughing, and skin irritation.

Heating PG at an extreme temperature converts it to a cancer-causing compound known as carbonyl. The Universal Plant never recommends any CBD vape products that have PG in it. If you do decide to purchase product with PG in it, to avoid respiratory implications, always stick to high-quality e-cigarettes from reputable suppliers. Properly made heating coils do not burn at the temperature needed to convert PG into carbonyl.

What About Side Effects of Terpenes?

If you’re not familiar with terpenes, this refers to a class of oily substances secreted by the cannabis plant. Many plant species actually produce terpenes, but in recent years the term has largely become associated with the cannabis industry.

CBD makers denature the terpenes, turning them into various terpenoids, each with their own distinct flavor. Some terpenoids also interact with the cannabinoids, which can amplify or hinder their effects. Breeders are constantly at work to try to produce terpenoids with desirable flavoring and bioavailability-assisting traits.

Since some terpenes enhance the CBD’s potency, they may also enhance the side effects. The same goes for the side effects associated with the psychoactive compound THC. Industry insiders have referred to this as the “entourage effect.”

As far as the terpenes themselves causing side effects, there aren’t any studies at this point suggesting they cause adverse reactions.

Side Effects from Other Ingredients

You also need to be mindful other additional ingredients. For CBD oil, that includes the carrier oil. For vape juices, this also includes thinners.

Carriers almost always include some sort of MCT oil, such as coconut or palm kernel oil. For the most part, these oils are healthy and have minimal side effects. Adverse reactions are minimal and usually only experienced briefly by first-time users. Minor side effects include: nausea, vomiting, diarrhea, and upset stomach. These sensations are also more likely to occur if you consume the oil on an empty stomach.

For vape juices, additional ingredients include thinners, either in the form of vegetable glycerin or propylene glycol. Let’s examine these two separately.

Vegetable glycerin (VG)

Side effects appear to be minor and usually include a mild headache, nausea, and vomiting.

Propylene Glycol (PG)

We discussed PG earlier and how it may convert into dangerous cancer-causing agents. In addition, a 2014 report4 found that vapor-based PG may cause dry cough and mouth and throat irritation. Some people also report skin irritation when their skin is exposed to PG in vapor or liquid form.

CBD Side Effects ≠ THC Side Effects

Okay, now let’s talk about THC, which has some more noteworthy side effects. As the psychoactive compound, this is the cannabinoid that produces the high and trippy sensation. What are some of the side effects of THC when taken above the 0.3% legal limit?

One of the most widely reported reactions is anxiety. This is due to THC’s biphasic effect. This means it produces a sensation in a low dose and the opposite sensation in higher concentrations. Whereas a small dose may calm the nerves, a higher dose induces the jitters, mood swings, and mild paranoia.

Some of the other side effects include:

  • Dry mouth – this is because there are CB receptors inside the mouth
  • Dry eyes – THC dilates blood vessels in the eyes, leading to dryness and redness
  • Lethargy – some people actually find this feeling helpful as it helps them relax. However, during the day, it can impede day-to-day activities. High THC content is found in the cannabis strain indica, which is known for its sedative effects.

Some lesser-reported side effects include:

  • Headaches
  • Vertigo
  • Difficulty breathing
  • Short-term memory loss
  • Increased heart rate

Some of these side effects, such as dry mouth, is also associated with CBD. However, any overlapping effects appear to be far more pronounced and frequent among THC users.

According to studies, prolonged THC use may also increase risk of some psychiatric disorders, such as schizophrenia.

CBD Oil Side Effects from Full-Spectrum Products

Of course, CBD and THC are only two of the estimated 100+ cannabinoids. What if you’re using a full-spectrum product? Do any of the additional cannabinoids cause side effects of their own?

Some of the other cannabinoids common in a full-spectrum oil include cannabinol (CBN), cannabigerol (CBG), and tetrahydrocannabivarin (THCV). Studies on these cannabinoids are limited. Many of the benefits also overlap with CBD. We can deduce, therefore, that any potential side effects include much of the mild reactions associated with CBD use.

The only standalone side effect we are aware of is an anorectic effect associated with THCV. This means it may reduce appetite. In most cases, this is a good thing as it may be a beneficial weight loss aid. However, some people also take cannabis for pain relief as part of their cancer treatment. Chemotherapy often causes appetite loss. With that in mind, any substance that causes further loss of appetite may be counterproductive. CBD, by contrast, is known to stimulate appetite, hence why cannabidiol is often said to give you the “munchies.” It’s another reason CBD is useful for cancer patients.

Where to Buy CBD Oil

To minimize side effects of CBD oil, always buy from a certified and reputable supplier. Buying a homemade oil from a friend of a friend is probably not the safest bet. You can’t be certain of the carrier oil or thinner used, or the presence of additional ingredients that may cause unwanted reactions.

Reputable suppliers always list the ingredients, which usually consist of no more than the cannabinoid extract, carrier oil, terpenes, and thinner if it’s a vape liquid.

Visit our Where to Buy section for a list of sellers we vetted and verified.

Final Thoughts on CBD Oil Side Effects

We don’t deny that some people will experience side effects. However, we wager that 95% of users won’t have such problems. For those that do experience unpleasant sensations, the effects are mild and temporary. The point we are trying to get across is that CBD is safe. You have nothing to worry about as long as you buy from a reputable supplier and stick to recommended dosages.

Medical References

Iffland K, Grotenhermen F. An Update on Safety and Side Effects of Cannabidiol: A Review of Clinical Data and Relevant Animal Studies. Cannabis Cannabinoid Res. 2017;2(1):139-154. [PMC]
Welty T, Luebke A, Gidal B. Cannabidiol: Promise and Pitfalls. Epilepsy Curr. 2014;14(5):250-252. [PMC]
Grayson L, Vines B, Nichol K, Szaflarski J, for the. An interaction between warfarin and cannabidiol, a case report. Epilepsy Behav Case Rep. 2017;9:10-11. [PMC]
Callahan-Lyon P. Electronic cigarettes: human health effects. Tob Control. 2014;23(Suppl 2):ii36-ii40. [PMC]