CBD Oil Side Effects

CBD Oil Side Effects

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CBD Oil Side Effects

Whenever using any type of supplement, it’s important to find out what side effects it may have, and CBD is no exception.


CBD is actually known to have a relatively safe side effect profile.

Its highly safe side effect profile is one of the reasons it’s being promoted by the medical community for things like epilepsy (versus other types of drugs with more potent side effects).

That being said, CBD does have some side effects and may interact with other medications or have effects on patients with certain conditions, so we’re going to discuss them here.

What are the most common side effects?

CBD is known to have the potential for treating a wide array of health conditions.

The compound belongs to a broad classification known as cannabinoids, which are found both in cannabis (phytocannabinoids) and the human body (endocannabinoids).

The cannabinoid, although derived from the cannabis plant is largely non-toxic, however.

CBD is generally regarded as safe. It exerts its effects on the body in a myriad of ways, mostly via CB1 and CB2 receptors of the endocannabinoid system.

It also interacts with other receptors such as serotonin and vanilloid receptors.

Recent research indicates that the use of CBD oil can sometimes trigger a number of side effects. These include, but are not limited to the following physical symptoms:

  • Diarrhea
  • Dizziness
  • Drowsiness
  • Dry mouth
  • Nausea

There’s also some concern from these studies that the use of CBD oil, especially over prolonged periods of time, may lead to increased levels of liver enzymes. This increase in liver enzymes is often a marker of liver damage or inflammation.

If you’re thinking of using CBD oil, it’s important to talk about potential side effects and adverse reactions with your doctor.

Another set of studies noted the following side effects which relate to mood or mental health:

  • Changes in mood
  • Fatigue
  • Changes in appetite

It’s important to note is that CBD oils may contain some THC. THC (the compound which produces the “high feeling”) may impair your ability to drive safely or operate equipment and may even have effects on your mood, memory, attention, and mental health.

It is also easy to consume too much CBD oil, so it’s important to start with a low dose, as it can take up to several hours or longer to begin to feel the effects after ingestion.

So, if you’re thinking of using CBD oil to treat a health problem (and it is legal where you live), make sure to consult your healthcare provider first to discuss whether it’s appropriate for you.

CBD also has some particularly interesting properties. These are the antioxidant, anti-inflammatory, neuroprotective, and anticonvulsant actions of the compound.

One peculiar fact about CBD is that it is a more potent neuroprotective antioxidant than both vitamin C and vitamin E. Research has even shown its slight effectiveness in treating cancer cells in vitro! (For more about that, read here).

Higher doses of the cannabinoid are believed to be helpful for treating some psychological conditions such as schizophrenia and dementia. Research on CBD in the areas of diabetes and nausea also show some promise.


Cannabis, in general, is known to be a safe and natural medicine, with almost no deaths associated with its use. Research consistently rates this herb as the least dangerous substance when compared to others such as alcohol and nicotine in regards to toxicity.

One problem with CBD is that since CBD oil products are largely not regulated, there’s no guarantee that any given CBD product contains a safe or effective level of CBD.

This is not just speculation, a 2017 study published in the Journal of the American Medical Association found that almost 70 percent of all CBD products sold online are not properly labeled, and could even cause serious harm to consumers.

A small amount of CBD oils may even have incorrectly labeled amounts of THC and other compounds. So always err on the side of caution.

Safety Profile of CBD

cbd side effects
cbd side effects

According to WebMD, CBD is considered “possibly safe” (according to medical professionals):

“Cannabidiol is POSSIBLY SAFE when taken by mouth and appropriately in adults. Cannabidiol doses of up to 300 mg daily have been used safely for up to 6 months. Higher doses of 1200-1500 mg daily have been used safely for up to 4 weeks. Cannabidiol sprays used under the tongue have been used in doses of 2.5 mg for up to 2 weeks. “

When using CBD there are a few special precautions & warnings that one needs to take into account. Most notably, during pregnancy and breastfeeding.

My Experience With CBD Side Effects

While I haven’t experienced any life altering CBD side effects, I can personally atest to two of the aforementioned.

First I like to note that I have taken numerous CBD supplements daily for the past year of varying milligrams and forms, and I have not had a single bad experience.

If anything the few side effects I have experienced were minor nusances.

When I tried my first bottle of CBD oil I did experience a dry mouth. The effects were akin to not drinking water after engaging in a strenous activity, not nearly as bad as the dry mouth experianced after taking certain medications. There was no negative “medicated” feeling associated with it.

The more I have taken CBD products, the more I noticed that the dry mouth goes away, it has not been nearly as noticeable as the first time I took CBD.

I might add,

I have noticed that CBD products of high potency and generally products with higher bioavailability, tend to have a more noticeable “dry mouth” feeling.

The last minor side effect I experienced was nausea.

What’s more

I only attained this side effect after taking a large dose of CBD (Approximately 300mg), and it was a very mild nauseous feeling, nothing to go run to the toilet bowl about.

Other than these two minor side effects, I have not had any severe bad experiences in my lengthy time taking CBD products.

That doesn’t change the fact that others may react differently.

Using CBD During Pregnancy

When it comes to using CBD during pregnancy, it’s generally cautioned against doing so.

A recent report from the American Academy of Pediatrics (AAP) that was published in the journal Pediatrics warns pregnant women and those nursing to avoid marijuana use due to possible adverse developmental effects on their child.

A study that was reviewed for the report showed that exposure to CBD during pregnancy was found to make the placental barrier more permeable, potentially placing the fetus at risk of certain substances.

WebMD (whose content is reviewed by certified physicians) cautions that while pregnant you should stay on the safe side and avoid the use of CBD. They warn that the information currently available is not enough.

CBD Interaction with Medications

CBD is also known to interact with some medications. So before you start taking CBD oil, discuss it with your physician to ensure your safety and avoid potentially harmful interactions with medications you’re already taking.

These concerns regarding CBD’s interaction with medications are grounded in the results of research in which these interactions were unveiled.

It is not known that CBD oil may interact with several medications. This includes some types of anti-epileptic drugs.

Much like any other substance you could introduce into your system, CBD has its own set of side effects and interactions.

Although these interactions aren’t necessarily serious, they are worth knowing if you take CBD, or plan on doing so in the future.

Overall, these side effects and interactions seem quite minor.

The authors of the study reviews state that CBD has a better side effect profile in comparison to other drugs used in the treatment of the medical conditions mentioned above.

CBD Effects on the Body

Another review of studies on CBD, this one published in the journal Current Drug Safety, stated that CBD has no adverse effects upon physiological parameters, in contrast to some other studies. The parameters referenced were heart rate, blood pressure, body temperature, and other such as gastrointestinal transit, and food intake.

The majority of side effects regarding CBD have been seen in vitro (meaning outside a living organism, such as Petri dishes or test tubes) and in animal studies.

These in-vitro side effects include affecting cell viability, reducing fertilization capacity, and inhibiting liver drug metabolism to some extent.

Because these studies were not conducted on humans, further research using human participants is needed to see if these side effects occur in humans.

This is because research conducted on animals doesn’t always correlate directly with that of humans, though it sometimes may.

Although some animals do have endocannabinoid systems, the route of administration in studies is usually different from that used by humans.

A majority of human studies involve oral administration or inhalation of CBD, whereas animal studies usually involve injection into blood.

These differences in administration routes can lead to varying blood concentrations of CBD, and hence different outcomes.

One major and important side effect of CBD to be cautious of is its effect on drug metabolism in the liver. This is particularly of importantance for anyone on pharmaceutical medications.

This is because CBD has been shown to interact with drug-metabolizing enzymes such as the well known cytochrome P450 family. Almost 60% of all pharmaceutical drugs are metabolized by cytochrome family enzymes after being ingested.

It also happens that this enzyme is responsible for metabolizing CBD as well.

Some pharmaceutical drugs may inhibit this enzyme, which can slow the breakdown of CBD considerably and even increase its physiological activity.

Moreover, some pharmaceutical drugs can increase levels of this enzyme, leading to a faster than normal breakdown of CBD.

So, if taking any pharmaceutical drugs, you should probably talk to your physician before taking CBD.

In the majority of cases, CBD’s interactions may prove to be only a minor issue, or no issue at all.

It’s notable that CBD also has beneficial actions on liver enzymes, such as increasing levels of enzymes in the cytochrome system, which are capable of breaking down cancer-causing substances like benzopyrene.

CBD’s Effect on Patients with Specific Conditions:

The currently defined risks of cannabis use largely inhabit the domain of mental illness.

cbd side effects
cbd side effects

THC, the psychoactive component of the cannabis plant, has been shown to agetate mental conditions in some people.

Now, CBD is mostly taken in an extracted or isolated form, derived from industrial hemp or strains with low quantities of THC.

CBD, unlike THC is actually not even psychoactive and has even been shown to be antipsychotic.

A 2017 review published within the scientific journal Cannabis and Cannabinoid Research discusses the safety and side effects of CBD based on studies on human subjects.

The review documents the use of CBD in many clinical studies, most of them regarding the condition of epilepsy, in addition to psychotic disorders.


From the review, the side effects of CBD administration were shown to be tiredness, diarrhea, and changes in things such as appetite and weight.

Some research suggests that taking high doses of cannabidiol might make muscle movement (or tremors) slightly worse in Parkinson’s disease patients.

Despite CBD being well tolerated and considered largely safe, it may cause adverse reactions in some people.

CBD’s effects on movement disorders are also notable.

In one study in particular, minors with refractory epilepsy treated with CBD showed aggravation of seizures and sleepiness. They also showed signs of digestive problems and some irritability.

Another recent study published in the International Journal of Neuroscience discusses the administration of CBD to patients with dystonic movement disorders. Oral doses of the cannabinoid ranging from 100–600mg per day were given over a long period along with standard medications to study their effects.

The results were that improvements in movement disorders were observed in patients, but some side effects were observed.

These side effects were hypotension (commonly known as low blood pressure), dry mouth, psychomotor slowing (which is the reduced ability to control motor reflexes), lightheadedness, and sleepiness.

On the other hand, when the dosage surpassed 300mg per day, it actually increased resting tremor. This led researchers to believe that CBD has Parkinson-aggravating effects.

In contrast, another study published in the Journal of Psychopharmacology showed that CBD is capable of improving the quality of life in people with Parkinson’s disease.

Many cannabis or CBD smokers are familiar with the side effect of dry mouth. This side effect is not major and can be rather easily solved with liquids such as glass of water or juice.

The reason dry mouth occurs is because cannabis reduces saliva secretion. Cannabinoid receptors are actually present within the salivary glands. CBD binds to these receptors, leading to the inhibition of salivary secretion, and hence leading to dry mouth.

What about the Possibility of Overdose?

Cannabinoids such as CBD have been largely shown to be exceptionally non-toxic, with no fatalities reported from their use.

Even in large doses such as those of up to 1500mg per day of CBD, there haven’t been any major effects shown, and they’re well-tolerated in human subjects.

The US Department of Health and Human Services has reported that no signs of toxicity or serious side effects occur, even with prolonged use of CBD in healthy individuals.


So in summary, the most common side effects of using CBD are drowsiness, dizziness, dry mouth, and nausea.

In general, these side effects are experienced to a minor degree, and in most cases CBD can be taken without any serious side effect even in large doses.

If you take any medications, you may want to be careful when taking CBD as it may interact with the compounds in the medications themselves. This is especially true for epilepsy patients.

Pregnant women should also avoid using CBD as per the advice of medical professionals.

If you suffer from any major diagnosed condition, CBD may also have an effect on your condition, so always consult a physician.


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