What Is CBD (Cannabidiol)?

CBD 101: An in-depth guide to CBD side effects, health benefits, and how it works in the brain and body.

In recent years, the public has become fascinated with CBD. Also known as cannabidiol, it’s one of the major ingredients in marijuana – and it’s suddenly appearing everywhere: in oils, vape pens, tinctures, as well as supplements.

But what is CBD? Are there really health benefits associated with it? There are benefits, but in order to make the most of them, it’s essential to understand how cannabidiol works.

What Is CBD

The Science Behind CBD

CBD is one of the primary active ingredients in marijuana. While it has spent years in the shadow of THC (which is well-known for its intoxicating high), the effects of CBD are just as important when it comes to how marijuana makes people feel. To comprehend how cannabidiol affects the brain and body, it helps to understand cannabinoids.

How Does CBD Work?

Back in the early 60s, a group of Israeli researchers led by Dr. Raphael Mechoulam decided to conduct tests on marijuana to figure out how it worked. By then, scientists had discovered that morphine was the active ingredient in the opium plant and that cocaine was the highly addictive substance in cacao leaves, but they still had no idea what caused the signature high when someone ingested marijuana.

The first ingredient they isolated in cannabis was CBD (they wouldn’t find THC until about a year later), and along with THC and dozens of other compounds in marijuana, it’s classified as a cannabinoid.

What are cannabinoids? They plug into the receptors in the brain to create various side effects. For example, THC binds to CB1 and CB2 receptors to make people feel high, happy, or sleepy. While CBD doesn’t bind well with either of those receptors, it indirectly affects them by stimulating the body to create its own cannabinoids (known as endocannabinoids). It also acts on non-cannabinoid receptor systems to create relaxation and kill pain.

CBD & the Entourage Effect

Mechoulam and his team noted that while each cannabinoid had a specific effect when used individually, they seemed to work better when used together. CBD features none of the intoxicating effects of THC. Also, when CBD and THC are used at a 2:1 ratio, the combination cancels out the high created by THC. This means that patients can use THC to quell their nausea or stimulate their appetites without feeling intoxicated, experiencing a fast heartbeat, or dealing with anxiety. Mechoulam named this phenomenon “the entourage effect” and it’s one of the reasons why medical marijuana proponents push hard for legal use of whole-plant cannabis. While minor cannabinoids such as CBC and THCV may not have noticeable effects, they work in subtle ways to boost their cannabinoid siblings.

CBD Side Effects

As CBD has gained more attention, people want to know more about its effects. Does CBD create a high if it’s isolated and consumed as a concentrate (in an oil, for instance)? Does it have any negative side effects? As with any substance, it’s important to know what to expect before consuming high doses of CBD oil or any type of concentrate.

Potential CBD effects include: 
  • Relaxation
  • Drowsiness
  • Light-headedness
  • Dry mouth
  • A drop in blood pressure
  • Diarrhea
  • Changes in appetite

What does CBD feel like? CBD doesn’t create a high the way ingesting a THC-rich marijuana strain does. Instead, it often leaves users feeling clear-headed. Many people report feeling a general sense of relaxation and well-being after they take it by itself or use a high-CBD strain of cannabis.

Because everyone’s brain, body, and metabolism are different, there’s no guarantee what the effects of cannabidiol will be. Doses of up to 600 mg are considered a good place to start and studies show they’re generally well-tolerated. It’s rare to hear of negative side effects with CBD, but as with any drug, it’s best to start with a lower dose and give it time to determine its effects. Generally, people find that the benefits far outweigh any negative side effects. If someone did take a large enough dose to create a “CBD high,” it would likely consist of feeling lightheaded and sleepy.

CBD Precautions

While studies have shown CBD to be well-tolerated and safe, it should be treated like any other drug or supplement. This means that people with health conditions should talk to their doctors before using CBD (whether in whole-plant marijuana or any form). This includes:

• Women who are pregnant/breastfeeding:
At this time, there’s not enough reliable information to know whether or not CBD may pose a risk to a fetus or breastfeeding infant.

• Those taking pharmaceutical drugs:
Because CBD interacts with the body’s cytochrome P-450 system, anyone taking medications should talk to their doctor or pharmacist about any potential interactions.

Why Combine CBD & THC?

While CBD is a useful cannabinoid in its own right, it’s even more useful when it’s combined with THC. This is because of the way the two compounds behave when paired together.

People use THC to treat many different diseases and disorders. Cancer patients, for example, have found that THC can help reduce the nausea and vomiting they experience after a strong dose of chemo. For some, though, the psychoactive effects of THC are too much. They need to go about their day without feeling high or can’t stand how THC sends their heart rate and anxiety levels skyrocketing.

When CBD is added into the equation, the side effects of THC that aren’t helpful in medical treatments begin to lessen. At a 2:1 CBD-to-THC ratio, the psychoactive effects of THC disappear entirely. This feature of the “entourage effect” enables people to use THC as medicine without any of the unwanted side effects.

THC also helps CBD out by making it work better at treating certain conditions. Parents of children with Dravet syndrome (a severe type of childhood epilepsy) have discovered that high doses of CBD can help where no other medications can. For some kids, however, a mix of THC and CBD gets the best results.

Watch: CBD Works Differently Than THC, Here’s How

Medical Benefits

Over the last couple of decades, laws have been passed that legalize medical marijuana (including CBD oil and concentrates) in a growing number of places. As the medical use of cannabis continues to spread, so do stories about its efficacy for a wide variety of conditions.

To get the proper medicine, however, it’s essential that patients understand which conditions CBD is effective at treating as opposed to ones that are better treated with THC. Studies are revealing that CBD is useful for treating diseases and ailments that range from anxiety to epilepsy.

General Medical Uses for CBD

While cannabidiol is showing promise as a treatment for many different medical conditions, it’s not a cure-all. To find out what conditions CBD can actually treat, as well as the ones for which it’s potentially effective, it helps to look at what the science says. Study after study has shown that CBD health benefits are wide-ranging. The compound shows promise for the following uses:


CBD has been studied as an anti-inflammatory for conditions such as rheumatoid arthritis. In this disease, inflammatory responses in the body cause pain and swelling. In studies on mice, CBD showed immunosuppressive and anti-inflammatory properties that stopped the progression of the disease.


Studies also back up the use of CBD as an anti-anxiety medication. Scientists found that CBD reduced stress-induced ulcers in mice. In a study on humans, CBD worked just as well as drugs like diazepam to reduce anxiety. In addition to anxiety in general, researchers found that CBD blocks the anxiety produced by THC.


While clinical trials on humans are still ongoing, past studies have shown promise that CBD may be an effective antipsychotic for people with conditions such as schizophrenia. In animal models, scientists noted that high-dose CBD did not create negative side effects associated with common antipsychotic pharmaceutical medications.


Anandamide, also known as “the bliss molecule,” is a chemical naturally found in the brain. It binds with cannabinoid receptors there and acts as a mood-booster. CBD slows the brain’s breakdown of anandamide, therefore acting as a natural antidepressant.


In addition to all of this, preclinical studies have shown that cannabidiol may fight cancer – at least in in a laboratory setting. In certain types of cancer, it kills the cells, stops them from growing, and prevents them from developing new blood vessels. More studies are necessary to see how this might be translated into medical treatments for people battling cancer.

Scientists are conducting a slew of studies to determine whether humans can use CBD to battle everything from chronic pain to opioid addiction. While many studies show promise, it’s important for people to talk to their doctors before modifying their medical treatment. It’s also important to put studies about CBD health benefits into context in terms of concentrations, dosage, and application methods that were used, as well as whether or not the tests have been successfully conducted on humans.

CBD and Dravet Syndrome

One of the most high-profile benefits of CBD has been for kids with a severe form of epilepsy known as Dravet syndrome. The disease begins in infancy, causes frequent and severe seizures, and can be debilitating and even deadly.

In recent years, parents and doctors have started exploring potential CBD benefits for little ones with Dravet syndrome. Several years ago, CNN’s Dr. Sanjay Gupta highlighted the story of Charlotte Figi in his four-part documentary series Weed. Her family had tried everything from diets, acupuncture, and dangerous drugs to stop Charlotte’s devastating seizures when they learned about high-CBD cannabis for epilepsy.

While getting the marijuana to treat their little girl was an uphill battle, once they did, the improvement in Charlotte’s condition was dramatic. Her story created a meteoric impact in the cannabis community, and the high-CBD cannabis strain that changed her life now carries her name: Charlotte’s Web.

Since then, a growing number of parents have found similar success using CBD (or a combination of CBD and THC) for their children’s condition. Studies conducted in the years since have confirmed these results. A 2017 trial of cannabidiol for drug-resistant seizures showed that it reduced the frequency of seizures of all types.

Watch: CBD and Dravet Syndrome – Dr Sanjay Gupta (CNN Special)

CBD Based Pharmaceuticals

Based on those initial studies, pharmaceutical companies started looking hard at the potential of CBD as an epilepsy treatment. Their goal was to harness the benefits of CBD in an isolated and concentrated form. In June of 2018, the U.S. Food and Drug Administration approved Epidiolex, produced by G.W. Pharmaceuticals, for use in children ages two and older who have seizure disorders. Epidiolex is a plant-based CBD pharmaceutical – essentially a purified, prescription-strength CBD. The FDA specified that its approval was for Epidiolex and not for CBD in general.

Later that year, the Drug Enforcement Agency rescheduled Epidiolex from a Schedule I drug (a category that includes substances such as cocaine and heroin) to Schedule V, the least-restrictive category of controlled substances. This paved the way for G.W. to start selling Epidiolex while drawing criticism from cannabis advocates because CBD itself remains categorized as a Schedule I substance. Although authorities haven’t begun a crackdown on businesses selling CBD oils and other products, marijuana proponents would like to see the compound rescheduled along with its pharmaceutical counterparts.

CBD also plays a major role in nabiximols (Sativex), an oral spray approved for muscle spasticity and neuropathic pain in patients with MS, as well as cancer pain. Sativex contains a 1:1 THC-to-CBD mix. Many patients report that the combination of the two cannabinoids provides noticeable relief of their symptoms. They also like that they can better control their dosage via the oral spray.

CBD in Marijuana vs Hemp

What’s the difference between CBD from marijuana versus the one from hemp? The answer is that high CBD marijuana strains may contain various amounts of THC, while hemp contains almost none of the psychoactive substance.

For years, many people only thought of marijuana as a way to get high, but cannabis growers are working wonders with plant genetics to create potent non-intoxicating medicine. Marijuana can be selectively bred to contain higher levels of CBD and lower levels of THC. This gives greater flexibility to medical or recreational users hoping to harness the effects of CBD while avoiding the high of THC.

While high-CBD strains such as Charlotte’s Web have been a game-changer for kids with Dravet Syndrome, if the levels of the THC in a strain are greater than .3%, it’s deemed illegal by federal U.S. law and subject to a crackdown in states where marijuana isn’t yet legal. For people who live in these areas, concentrates derived from hemp (the non-psychoactive form of cannabis) allow consumers to take advantage of the benefits of CBD.

Common Ingestion Methods

What’s the best way to use CBD? People use a variety of methods to ingest cannabidiol, but before beginning, it’s important to understand an important concept – and that’s decarboxylation.

Understanding Decarboxylation

While it sounds like a complex science term, decarboxylation simply means heating marijuana long enough to activate the cannabinoids inside. In its raw form, cannabis contains CBDA, or cannabidiolic acid. When CBDA is heated to its boiling point, it becomes cannabidiol (or CBD).

To decarb raw marijuana flower and activate its CBD, simply break up the cannabis buds until they’re in small pieces and put them in a single layer on a baking sheet (making sure to cover the entire sheet). Bake it for up to 40 minutes at 230 degrees Fahrenheit, stirring the material every 10 minutes until it turns a medium brown color.


For thousands of years, people have used a marijuana consumption method that both decarboxylates their cannabis and provides an easy ingestion method: they set it on fire and inhale the smoke. While inhalation of smoke may pose certain health risks, smoking high-CBD marijuana strains is an easy and effective way to take advantage of CBD’s benefits and many effects.


Especially for medical users who would like to ingest in a cleaner, more healthy fashion than smoking it, vaporizing provides an excellent alternative. Vaporizers heat cannabis material through one of two methods: conduction or convection. With conduction, the flower (or wax/oil) is placed directly against a heating source. Convection heating involves surrounding the CBD-rich material with hot air. Either way, the goal with vaporizing is to heat the material until it releases vapor and not to the point that it combusts and releases harsh smoke.


Because cannabinoid receptors are located not only in the brain but throughout the body, topical products are another way to take advantage of the effects of cannabidiol. Studies have found that topical cannabinol is helpful for reducing the pain and inflammation of arthritis, so rubbing on CBD-rich oils and creams can help.


CBD oils have become increasingly popular over the past few years. Consuming oil one of the easiest ways to take advantage of the health benefits in a concentrated form. To get the oil, manufacturers use a solvent (often something like ethanol) to extract the cannabinoids from the plant material. After they evaporate the solvent, they’re left with CBD-rich oil.

Depending on what plant the oil comes from (marijuana or hemp?), it may have some THC or practically no THC at all. It’s important to note that some CBD oil is meant to be taken orally while others are meant to be vaped. Getting them mixed up can have negative results. For example, if oral oil is vaped, it can cause illness by introducing substances such as olive oil into the lungs.



What is CBD?

Otherwise known as cannabidiol, CBD is one of the cannabinoids (or active ingredients) found in marijuana. Unlike THC (another primary cannabinoid in marijuana), CBD does not get people high. It plugs into the CB2 receptors in the endocannabinoid system of the brain to create feelings of subtle relaxation.

Can CBD get you high?

No. Unlike the THC in marijuana, CBD is not psychoactive. This means that it leaves people feeling clear-headed and does not cause any intoxication. This is one of the reasons why medical patients use it: unlike many pharmaceutical drugs, the benefits of this cannabinoid greatly outweigh any slight side effects.

What do CBD effects feel like?

At low doses, the side effects are unnoticeable. Higher doses may cause relaxation or slight sleepiness. Very high doses can make some people feel light-headed or a bit “out of it,” which is why it’s best to start with lower doses at first.

Does CBD show up on a drug test?

Since drug tests are used to look for psychoactive THC (tetrahydrocannabinol) only, CBD won’t cause you to fail a drug test. However, if you take a CBD oil that has small amounts of THC in it, the THC may show up on the test.

How is the latter possible? CBD oils made from marijuana plants (commonly found in states where weed is legal) can contain small amounts of THC, while CBD oil made from hemp plants have next-to-no THC.


Can I overdose on CBD oil?

There has never been a fatal overdose reported as a result of CBD oil. A 2011 study found that participants could tolerate doses of up to 1,500 mg a day. As the dose moves higher, however, lightheadedness and other unwanted side effects become more likely.

Can I vape CBD oil?

It depends. Edible oils should never be vaped, as they contain carrier oils such as butter, olive, and coconut oil that can cause illness if inhaled into the lungs. However,there are liquids that are manufactured specifically to be used in a vaporizer.

What kind of medications does CBD interact with?

Because cannabidiol causes a drop in blood pressure, people with low blood pressure or who take blood pressure medication should consult with their doctor about CBD.

CBD interacts with the body’s cytochrome P-450 system (an enzyme system in the liver), meaning that it can increase the levels of certain drugs in your bloodstream. Another substance that interacts with this system is grapefruit, so anyone taking a medication that interacts with grapefruit should be aware of possible cannabidiol interactions, as well.

A list of some (but not all) medications that use the CYP450 system:
  • Antiarrythmics
  • Antibiotics
  • Anesthetics
  • Angiotension II blockers
  • Antipsychotics
  • Antidepressants
  • Anti-epileptics
  • Antihistamines
  • Benzodiazepines
  • Beta blockers
  • Calcium channel blockers
  • HIV antivirals
  • HMG CoA reductase inhibitors
  • Immune modulators
  • NSAIDs
  • Oral hypoglycemic agents
  • PPIs
  • Prokinetics
  • Steroids
  • Sulfonylureas

Note: It’s always best for individuals to speak with their doctor before taking any supplement in combination with any medication.

Unlocking the Secrets of CBD

The benefits of CBD have demonstrated to the world that there’s more to marijuana than getting high. With manufacturers pulling it out of hemp and marijuana breeders putting more focus on high-CBD strains, the popularity of cannabidiol continues to rise. Recreational weed consumers are using knowledge about CBD to help customize their high. At the same time, medical patients are amazed at the relief they’ve received from their symptoms while experiencing little to no side effects.

Meanwhile, studies are continuing to confirm the stories that patients have told for years: for many conditions, CBD can be an effective medicine. With expanding legalization and further research, scientists will soon be able to unlock even more secrets from within this wondrous compound.

Dorothy Harris - CNBS Author: Dorothy Harris
Dorothy is far from being a pot-head. Actually, when we first met she wasn’t very familiar with cannabis - but with her excellent research skills and drive for knowledge, it didn’t take her long to master the field. Dorothy comes from a scientific background and is in charge of researching and writing our advanced scientific and medical topics, as their correctness is not something we are willing to compromise on. Dorothy specializes in top notch research, making sure no stone is left unturned.
About | Facebook | Twitter | Contact

Category Pages:Related Categories:
  • Cannabis 101 - Information about cannabis life, culture, and consumption methods.
  • Cannabis Types - A guide to the different types of marijuana: sativa, indica, hybrids, hemp, and ruderalis.
  • Concentrates & Extracts - An exploration of cannabis concentrates & extracts from BHO and beyond.
  • Cannabis & Health - A guide to the many benefits of marijuana, including medical and general health uses.

1 Comment
Inline Feedbacks
View all comments
1 year ago

Hey there. Typo In the first paragraph under How Does CBD Work? it says “…and that cocaine was the highly addictive substance in cacao leaves.” That should be “coca” leaves, not “cacao” leaves. Cacao is the plant we get chocolate from via the seeds. Coca is the plant we get cocaine from via the leaves. Just trying to help out! Great pages here! Thanks for creating this site!