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Is CBD Safe and Effective? What You Need to Know When Considering CBD

Is CBD Safe and Effective? What You Need to Know When Considering CBD

Cannabis is an extraordinary plant with many practical purposes. It can be spun into rope or clothing. Pain-relieving medicinal oil can be pressed from it. Nutritious protein powders can be derived from the seeds. Processed correctly, it can even become biofuel for cars! 

Yet, what makes cannabis genuinely unique is the fact that it has several molecules that fit perfectly into human pain receptors, causing a cascade of changes all over the human body. For example, many studies in the last decade have isolated the chemicals cannabidiol (CBD) and tetrahydrocannabinol (THC) from cannabis, substances that are highly active in the human body (1). Think about that relationship for a moment. If a receptor for some molecule exists in the body, it is because a chemical produced by the human body fits in it, as a key fits into a lock. Isn't it curious that a plant produces the same pain-relieving "key" as the human body?

CBD Interaction with the Human Endocannabinoid System (ECS)

The human endocannabinoid system (ECS) is a special type of internal messaging system that produces chemical messengers that react with the receiving mechanism for those chemicals:

Endocannabinoids - These are chemical messengers produced by the human body that act as the "keys" that trigger changes in the receptors. The prefix "endo-" indicates that these cannabinoids are produced within the body. Endocannabinoids are produced in the central nervous system, some organs, and some immune cells.

Receptors - Receptors are unique places on the surface of cells that receive the keys (the "locks" in our analogy), which initiate a series of changes once a key fits into it. These receptors are on the surface of cells all over the body. They're found in the nervous system (including the brain and nerves reaching out to the limbs), the heart and other specific organs (2), microglia cells in the immune system (3), and different types of tissues such as bone, skin, and muscle (4).

CBD and THC are two of many active compounds found this plant. Cannabis is rife with chemicals, containing over 500 identified chemicals, with over 100 active compounds labeled cannabinoids (1). CBD and THC are just two cannabinoids that interact with the human endocannabinoid (ECS) system. 

This lock and key relationship means we can supplement plant-derived CBD to intentionally trigger changes that occur naturally within our own bodies, including pain relief.

When cannabinoids or endocannabinoids fit into their receptors in the nervous and immune systems, they can influence many aspects of the human body, from rates of inflammation and appetite levels to the formation of memories and even how pain is perceived (5, 6).

The ECS is a complex and fascinating system still being explored today. Likewise, cannabis studies continue to isolate and test its compounds for therapeutic purposes, attempting to quantify and verify its wide-ranging effects on the human ECS.

A Time-Tested Plant

Interestingly, the recreational and medicinal use of cannabis goes way back in human history, so there is a lengthy body of anecdotal evidence that humans have used it for a variety of purposes for a long time. There is evidence of cannabis being used by Indo-Europeans as long as 5,000 years ago (7). In India, cannabis use dates back thousands of years and is still a part of Ayurvedic medicine "to reduce pain, nausea, and anxiety, improve appetite and sleep, relax muscles, and produce a feeling of euphoria” (8). Several thousand years ago, cannabis appeared in China as an anesthetic and in Egypt as an anti-inflammatory (8). What are the current claims of health benefits? What has research uncovered?

Benefits - Anecdotes and Research

Anecdotally in doctors' offices across America, CBD has alleviated many symptoms and conditions.

Those with ADD/ADHD can have increased focus as they become more relaxed. Topical CBD preparations have reduced the inflammation of various skin conditions. Nighttime formulations have helped people reset their biological clocks and get refreshing sleep.

Meanwhile, researchers are busy quantifying CBD's powers through scientific testing and have found the following benefits in animal and/or human studies (3, 9):

  • Relieves pain, including chronic pain

  • Reduces inflammation (rodent study)

  • Addresses insomnia 

  • Treats arthritis topically 

  • Reduces anxiety 

  • Decreases symptoms of depression (rodent study)

  • Some positive impacts on different neurodegenerative diseases

  • Relieves epilepsy symptoms

  • Addresses seizures in rare conditions (Dravet Syndrome, Lennox-Gastaut syndrome)

  • Creates some positive results for schizophrenia and autism

  • Eases spasticity related with multiple sclerosis 

  • Combats addiction 


One of the significant concerns about cannabis products is their psychoactive effects, the ability to cause intense euphoria, impair thinking, and affect reflex times. 

THC is the cannabis compound that has strong psychoactive effects, the one that is primarily responsible for the "high" when smoking the cannabis plant. CBD, on the other hand, is one of the least psychoactive substances isolated from cannabis. 

That is one of the benefits of the isolation of the CBD compound - the ability to affect the ECS to relieve pain and other therapeutic uses without the mind-altering effects of THC.

However, it should be noted that THC combined with CBD has additional positive impacts on the body, called "the cohort effect." As a result, many CBD products now add THC in increments, allowing dosages to be altered. Unfortunately, taking too much THC can have serious repercussions. Some people are very sensitive to THC, and even small amounts can make them very uncomfortable. 

While taking too much CBD is only likely to cause drowsiness or dizziness, taking too much THC can exacerbate psychotic symptoms, cause a racing heart (tachycardia) (10), induce paranoia (11), or increase anxiety (11). CBD, on the other hand, tends to do the opposite - inducing relaxation, reducing anxiety, and alleviating some symptoms of psychoses (3).

What's the Down Side of CBD?

While CBD is legal to use in all states and can be bought "over the counter," it is a compound that should be treated with respect. There's a long list of benefits, but some cautions to consider as well:

1. If taking medications, consult a doctor. CBD is broken down by enzymes in the liver, which also break down and process medications. The metabolism of CBD could slow the metabolism of medications, reducing their efficacy or having other interactions with them. Those taking medications to thin blood, address heart conditions, or suppress the immune system should be extremely cautious about taking CBD (6). If taking any medications, please check with your doctor before taking CBD.

2. Be very cautious with THC content. As mentioned previously, some people are extremely sensitive to THC. Many substantial benefits come from just the CBD, so if you suspect you might be sensitive, try the non-THC formulations first.

3. Pay attention to dosage. Start with a low dose and increase the dosage slightly each time it is taken to achieve the desired effect. Note that liquid forms are more fast-acting and wear off quickly, but capsules and tablets may take hours to reach their full effect. Wait to see how your body reacts before taking any more.

4. CBD can trigger a drug test. Most drug tests are not designed to distinguish CBD from THC, so even CBD with little or no THC can trigger a positive result on a drug test. If you are drug-tested as part of your employment, CBD may not be for you.

5. Consider quality. There are a lot of over-the-counter CBD products, but not all of them deliver what they claim on the package. Products without testing could contain mold or other harmful chemicals (13). Many reputable supplement companies are now formulating CBD products, complete with testing that shows the purity of the product and its efficacy. CBD products from long-established nutritional supplement companies may only be available through a healthcare practitioner. While slightly more expensive, the cost includes testing the product to ensure it is of high quality and has beneficial effects.

6. Don't use CBD if pregnant or breastfeeding. There are not a lot of good long-term studies about using CBD during pregnancy and the effects on the child afterward. It is well-established that what the mother consumes can pass through both placenta and breast milk. Until more safety studies are performed for this population, it's best to pass on CBD.

7. Be cautious if you have certain mental conditions. Interestingly, studies of the effects of CBD on schizophrenia are mixed in the medical literature, with some showing benefits and others showing increased symptoms. Ill effects may be dosage-related, with small doses being beneficial while higher dosages could trigger symptoms. Each individual has a unique inner chemistry, so there may be a range of reactions rather than one expected outcome. If you have been diagnosed with schizophrenia, borderline personality disorder, or other mental or cognitive condition, it is highly recommended to speak with a doctor before using CBD.

Consult a Doctor

As you can see, CBD has many benefits but must be used cautiously. While CBD does help people manage chronic pain, gain control of their sleep, or relieve their anxiety, it's not for everyone. If you think CBD might help alleviate your symptoms, make an appointment with the Temecula Center for Integrative Medicine. We'll help determine the root cause and discuss an individualized treatment plan. If CBD is an option, we'll help with dosage and figuring out if any medications you're taking might be negatively affected by CBD. Let's investigate your health situation together.


Jonathan Vellinga, M.D.

Jonathan Vellinga, MD is an Internal Medicine practitioner with a broad interest in medicine. He graduated Summa cum laude from Weber State University in Clinical Laboratory Sciences and completed his medical degree from the Medical College of Wisconsin.​

Upon graduation from medical school, he completed his Internal Medicine residency at the University of Michigan. Dr. Vellinga is board-certified with the American Board of Internal Medicine and a member of the Institute for Functional Medicine.




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5. Harvard Health. (2022, September 26). Beyond CBD: Here come the other cannabinoids, but where’s the evidence?

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8 Crocq, M. (2020b). History of cannabis and the endocannabinoid system. Dialogues in Clinical Neuroscience, 22(3), 223–228.

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10.Goyal, H., Awad, H. H., & Ghali, J. K. (2017). Role of cannabis in cardiovascular disorders. Journal of Thoracic Disease, 9(7), 2079–2092.

12. Freeman, D., Dunn, G., Murray, R. M., Evans, N., Lister, R., Antley, A., Slater, M., Godlewska, B. R., Cornish, R., Williams, J., Di Simplicio, M., Igoumenou, A., Brenneisen, R., Tunbridge, E. M., Harrison, P. J., Harmer, C. J., Cowen, P. J., & Morrison, P. (2014). How cannabis causes paranoia: Using the intravenous administration of ∆ 9 -Tetrahydrocannabinol (THC) to identify key cognitive mechanisms leading to paranoia. Schizophrenia Bulletin, 41(2), 391–399.

13. Department of Cannabis Control - State of California. (n.d.). What’s legal. Department of Cannabis Control.


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