* Free Shipping Over $99 *

CBD vs THC: Learn from a Pharmacist

Posted by Dr. Leslie Mudd, PharmD on Oct 4th 2020

CBD vs THC: Learn from a Pharmacist

CBD vs THC: How are they different?

Research from our Pharmacist

What are the differences between THC vs CBD? It’s a natural question to ask once you start to learn about the cannabis plant. If CBD comes from the same plant as THC, then why doesn’t it get you high? If it doesn’t get you high, then what the heck does it do? That's what you will learn in this blog post.

Hemp vs Marijuana

Cannabis, known either as marijuana or hemp depending on the THC level, is one of the most commonly used, grown, and consumed plants in the world today. But still, only people who are curious enough to do their own research know more about cannabis than “THC gets you high.” Yes it does, but there’s so much more to know. How does tetrahydrocannabinol (THC) differ from cannabidiol (CBD)? That’s what you will learn by reading this article.

By 2020, cannabis has been legalized for medical use in at least 33 states and the District of Columbia. Recreational marijuana is legal in at least 11 states and DC. At the federal level, the cannabis plant is legal only if the THC content does not exceed 0.3%, which defines it as hemp.

With hemp now legal again, consumers and researchers are becoming more interested in the clinical uses of cannabis. The plant contains multiple compounds that can potentially bring significant health benefits, including THC and CBD.

Both THC and CBD are cannabis-derived molecules and the two major cannabinoids produced by the plant. So if they come from the same place, why are they so different? What’s the difference between THC and CBD?1,2

Where do CBD and THC Come From?

CBD and THC are two of more than 120 naturally occurring cannabinoids found in the cannabis plant. Cannabinoids are naturally occurring chemical compounds found in cannabis,. The most common cannabinoids are THC, followed by CBD.

There are two main sub-species of cannabis plants, Cannabis sativa and Cannabis indica. Both sub-species contain significantly higher concentrations of THC than CBD. Traditionally, hemp plants were sativa varieties of cannabis that grew tall for fiber production. But the Farm Bill of 2018 changed the definition of hemp to mean any cannabis plant with a THC level below 0.3%.

This Congressional change of the definition of hemp is the source of confusion for many who thought of hemp only in a historical context. The hemp plants that create full spectrum CBD oils come from sativa-indica hybrids. That means they look and smell exactly like marijuana plants. The only difference is the THC level. Each variety of cannabis, whether marijuana or hemp, has a different ratio of cannabinoids, THC to CBD.3

Molecular Differences between CBD vs THC

When analyzing CBD and THC at a molecular level, they have similar structures but with key differences. Both compounds contain the exact same chemical formula, which contains 21 atoms of carbon, thirty of hydrogen, and two of oxygen. Their molar masses are also relatively identical with THC being 314.469 gram/mol and CBD being 314.464 grams/mol.

With these similar characteristics, one may think they are the same compound. However, the key difference between CBD and THC molecularly is how each is structured. THC contains a cyclic group within its chemical formula at a specific location. 

THC’s prefix “tetra-hydro” means that the molecule has four hydrogen atom substituents. By contrast, CBD is structured as a hydroxyl group. This seemingly small difference in molecular structure gives the two compounds entirely different properties.3,4

Effects of CBD vs THC on the Human Body

THC and CBD have different pharmacological effects within the human body. Both chemicals act upon the body through cannabinoid receptors, which are a part of the endocannabinoid system, or ECS. The ECS consists of a group of lipid proteins, enzymes, and receptors that play a role in many physiological processes that science is still studying.


However, CBD and THC play different roles within this particular system. THC acts upon certain cannabinoid receptors in the brain, CB1 receptors, to produce psychoactive effects and can produce the commonly known “euphoric high” effect. On the other hand, CBD does not contain any intoxicating properties and can actually reduces the euphoric effects of THC. That’s because CBD bonds with CB2 receptors elsewhere in the body, not in the nervous system.


More research is needed to identify certain areas of health benefit from each of the compounds. Preliminary literature demonstrates many potential heath advantages for each chemical. Medical marijuana is legal in at least 33 states with a wide variety of qualifying conditions, depending on the state. The wellness effects of CBD are potentially a lot broader due to its unique role in the ECS, but more research is needed.


Research demonstrates potential health advantages of CBD that are too numerous to list here, but include its possible use as a pain reliever, a sleep aid, and an anti-stress supplement.3 Research on the potential benefits of CBD and THC have been limited. However, there are some formulations of each compound that have been approved for certain conditions.2,5

Side Effects of CBD vs THC

Due to the differences between CBD and THC, they vary in their side effects as well. THC is inclined to have more dramatic adverse effects than CBD because of its psychoactive component. Some of the most common side effects for short term use include impaired short-term memory, dry mouth, and increased appetite.


On the other hand, CBD tends to be milder and more easily tolerated due to its lack of intoxicating components. The most common side effects seen with CBD use are drowsiness, appetite changes, increased liver enzymes, and sometimes even a rash. Overall, the side effects of CBD compared to THC are minimal and generally mild in severity.5,6,7


CBD and THC do have a few similarities in how they affect our bodies. You cannot overdose on CBD or THC, making them a much safer alternative for folks who are currently using prescription opioids or other painkillers. This of course is all dependent upon how bad your symptoms are, and how much CBD you will need to take to effectively treat them.

Differences in Legality of CBD vs THC

At least 47 states have legalized CBD products, following federal law. The passage of the Agriculture Improvement Act of 2018, commonly referred to as “the Farm Bill,” legalized hemp at the federal level, as long as the THC remains below 0.3%. As of 2020, only Idaho, South Dakota, and Nebraska have laws against possessing CBD products.

But still, the government considers THC to be a Schedule 1 controlled substance, keeping it illegal. Even thought at least 33 states have legalized THC products at the state level. In U.S. states where THC is considered a legal substance, it is still illegal federally. Federal law ultimately overrules state law.8  

Full spectrum CBD products, on the other hand, are fully legal as long as a lab report confirms that the THC level is below 0.3%, which is an arbitrary standard set by Congress. One day that law will change. But for now, that’s what it is.

Drug Testing: CBD vs THC

Conventional drug tests that are used for employment and criminal justice reasons are able to detect the presence of THC in the body by measuring one of its metabolites, 9-carboxy-THC, which is the primary psychoactive component of marijuana. However, this metabolite is not a derivative of CBD.6


So, should one be worried about testing positive for THC in a drug test? The answer is yes. Some drug tests are not sophisticated enough to distinguish between THC and CBD metabolites, and can trigger a false positive for THC as a result.


The only real solution to this problem of CBD users getting discriminated against for testing positive for legal cannabinoids is to change the drug-testing laws in America. Cornbread Hemp believes that the Americans with Disabilities Act should protect users of full spectrum CBD oil against discrimination by their employers. But as of 2020, a lawsuit that invokes the ADA to protect CBD users has yet to be filed.


If someone is anticipating a future drug test, that person should be careful. A person should assume they will test positive if they have taken CBD regularly within a month of a drug test.


To avoid negative consequences of a surprise positive on a drug test, get a note from your doctor saying you need to take full spectrum CBD. And then talk to your employer’s human resources department. Until laws and workplace norms become more understanding of full spectrum or broad spectrum CBD users, get everything in writing.9

CBD vs THC Conclusion

CBD and THC come from the same plant and their molecular structure is extremely similar. However, they have distinctively different effects within the human body. THC is known to be largely involved in the CB1 receptors of the ECS located in the brain and nervous system. CBD interacts mostly with CB2 receptors, found in tissues throughout the body. For this reason, the wellness properties and side effects differ between the two compounds.

The biggest difference is that THC gets you high, and CBD does not. CBD is widely held to be useful in both oil and tincture preparations for many wellness benefits that still require more scientific study. At least 33 states allow for the medical use of THC-rich marijuana. Even though CBD is legal under federal law, companies that sell CBD products cannot make medical claims until those claims are approved by the Food and Drug Administration.

With CBD now legal but unregulated, and many people trying to sell hemp seed oil disguised as CBD oil, it is important to understand where CBD products come from and how they are made. Always look for the following signs of a quality CBD product:

  • USDA organic seal
  • American-sourced hemp
  • QR codes that link to lab reports
  • Third-party testing for safety as well as potency

Follow these steps and you will be more likely to find a quality CBD product, like our USDA certified organic CBD oils from Cornbread Hemp — made from organic Kentucky hemp flowers extracted with organic sugarcane ethanol. This yields a robust full spectrum hemp extract that is high in CBD, with as much THC as federal law allows.



United Nations Office on Drugs and Crime, World Drug Report 2016, Vienna 2016.


Office of the Commissioner. FDA and Cannabis: Research and Drug Approval Process. Aug. 2020,


Kogan NM, Mechoulam R. Cannabinoids in health and disease. Dialogues Clin Neurosci. 2007;9(4):413‐


Pertwee, Roger G. “Cannabinoid pharmacology: the first 66 years.” British journal of pharmacology vol. 147 Suppl 1,Suppl 1 (2006): S163-71. doi:10.1038/sj.bjp.0706406


EPIDIOLEX – cannabidiol [package insert]. Carlsbad, CA: Greenwich Biosciences; 2018.


Volkow ND, Baler RD, Compton WM, Weiss SR. Adverse health effects of marijuana use. N Engl J Med. 2014;370(23):2219-2227. doi:10.1056/NEJMra1402309


Millar SA, Stone NL, Bellman ZD, Yates AS, England TJ, O'Sullivan SE. A systematic review of cannabidiol dosing in clinical populations. Br J Clin Pharmacol. 2019;85(9):1888-1900. doi:10.1111/bcp.14038


Office of the Commissioner. FDA Regulation of Cannabis and Cannabis-Derived Products: Q&A. Aug. 2020,


Urine Testing for Detection of Marijuana: An Advisory. Centers for Disease Control and Prevention. Published May 8, 1998. Accessed June 3, 2020