As the legal use of marijuana and other cannabis products grows, consumers are becoming more curious about their options. This includes cannabidiol (CBD) and tetrahydrocannabinol (THC), two natural compounds found in plants of the Cannabis genus.

CBD can be extracted from hemp or from marijuana. Hemp plants are cannabis plants that contain less than 0.3 percent THC, while marijuana plants are cannabis plants that contain higher concentrations of THC. CBD is sold in the form of gels, gummies, oils, supplements, extracts, and more.

THC is the main psychoactive compound in marijuana that gives the high sensation. It can be consumed by smoking marijuana. It’s also available in oils, edibles, tinctures, capsules, and more.

Both compounds interact with your body’s endocannabinoid system, but they have very different effects.

Read on to learn more about these compounds. While they may have a lot in common, they have some key differences that determine how they’re used.

Both CBD and THC have the exact same molecular structure: 21 carbon atoms, 30 hydrogen atoms, and 2 oxygen atoms. A slight difference in how the atoms are arranged accounts for the differing effects on your body.

Both CBD and THC are chemically similar to your body’s own endocannabinoids. This allows them to interact with your cannabinoid receptors.

The interaction affects the release of neurotransmitters in your brain. Neurotransmitters are chemicals responsible for relaying messages between cells and have roles in pain, immune function, stress, sleep, to name a few.

Despite their similar chemical structures, CBD and THC don’t have the same psychoactive effects. In fact, CBD is a nonpsychoactive compound. That means it doesn’t produce the “high” associated with THC.

THC binds with the cannabinoid 1 (CB1) receptors in the brain. It produces a high or sense of euphoria.

CBD binds very weakly, if at all, to CB1 receptors. In fact, it can interfere with the binding of THC and dampen the psychoactive effects.

In the United States, cannabis-related laws are evolving regularly. Marijuana and THC are on the list of controlled substances, so they’re prohibited under federal law.

However, many states and Washington, D.C. have passed cannabis-related laws making medical marijuana with high levels of THC legal. The marijuana may need to be prescribed by a licensed physician.

In addition, several states have made recreational use of marijuana and THC legal.

In states where marijuana is legal for recreational or medical purposes, you should be able to buy CBD.

Before you try to buy products with CBD or THC, get information about your state’s laws. If you possess cannabis-related products in a state where they’re illegal or don’t have a medical prescription in states where the products are legal for medical treatment, you could face legal penalties.

CBD and THC have many of the same medical benefits. They can provide relief from several of the same conditions. However, CBD doesn’t cause the euphoric effects that occur with THC. Some people may prefer to use CBD because of the lack of this side effect.

In June 2018, the Food and Drug Administration approved Epidiolex, the first prescription medication to contain CBD. It’s used to treat rare, difficult-to-control forms of epilepsy.

CBD is used to help with other various conditions, such as:

THC is used to help with conditions such as:

CBD is well-tolerated, even in large doses. Research suggests any side effects that occur with CBD use are likely the result of drug-to-drug interactions between CBD and other medications you may be taking.

THC causes temporary side effects, such as:

  • increased heart rate
  • coordination problems
  • dry mouth
  • red eyes
  • slower reaction times
  • memory loss

These side effects are part of the compound’s psychoactive properties.

Neither compound is fatal.

However, high THC use may be connected to long-term negative psychiatric effects. This is especially true for adolescents who consume large amounts of THC.

The effect on the brain is more profound for teens. Using the compound increases the risk for some psychiatric disorders, such as schizophrenia.

Cannabinoids like THC and CBD are stored in the body’s fat. They can show up on drug tests for several days or weeks after you use them.

Not every drug test will be able to detect CBD, but CBD-sensitive tests are available. Most standard drug tests will look for chemicals related to THC, so THC or marijuana use might show up on a screening.

Likewise, hemp can produce some THC in addition to CBD, so a test could be positive for THC even if you’ve not used it.

CBD and THC are two of the most prominent cannabinoids found in the Cannabis plant. Both marijuana and hemp produce CBD and THC.

However, marijuana has a higher concentration of THC. Hemp has a higher concentration of CBD.

The average marijuana strain today contains about 12 percent THC. CBD oil may contain small amounts of THC because it’s present in the hemp plant. CBD can have no more than 0.3 percent THC to be legal at the federal level.

CBD and THC both have medical benefits. They’re also both considered safe, but consider the possibility of side effects and interactions with other drugs you’re taking. Talk with your doctor if you have any questions.

CBDTHC
Hemp-derivedYESNO
Marijuana-derivedYES*NO
IllegalNO (See below)YES (See below)
Produce a “high”NOYES
Interact with endocannabinoid systemYESYES
Side effectsAlmost nonePsychoactive side effects
Shows on drug testPossibly**YES
Pain relieverYESYES
Reduces nauseaYESYES
Eases migrainesYESYES
Reduces anxietyYESYES
Eases depressionYESNO
Decreases seizuresYESNO
Anti-inflammatoryYESYES
Helps with insomniaYESYES
Helps with psychosisYESNO
Increases appetiteNOYES
Used for various other conditionsYESYES

* CBD can be extracted from hemp (cannabis plants that contain less than 0.3 percent THC) or from marijuana plants (cannabis plants with higher concentrations of THC).

** CBD isn't detected in hemp products, but hemp products may contain trace amounts of THC. THC may show up in high enough concentrations to produce a positive drug test.

Is CBD Legal? Marijuana-derived CBD products are illegal on the federal level, but are legal under some state laws. Hemp-derived CBD products (with less than 0.3 percent THC) are legal on the federal level, but are still illegal under some state laws. Check your state's laws and those of anywhere you travel. Keep in mind that nonprescription CBD products are not FDA-approved, and may be inaccurately labeled.