Cannabis contains over 113 different chemical compounds known as cannabinoids. Cannabidiol (CBD) and delta-9-tetrahydrocannabinol (THC) are two types of chemical compounds derived from cannabis. In recent years, interest has grown in the potential health effects and benefits of cannabis. Much of this interest has centered on these two cannabinoids.
This interest is likely to continue to grow as cannabis and marijuana products become legal in more states. A number of different products have emerged that contain CBD, THC, or both that are designed to alleviate ailments such as stress, anxiety, and insomnia. In order to understand the side effects and potential benefits of these products, it is important to first understand the differences between CBD and THC.
What Is CBD?
Cannabidiol, usually referred to as CBD, is the second most prevalent chemical compound found in cannabis. First discovered during the 1940s, CBD has recently become more popular as a natural treatment for a range of conditions. It can be derived from hemp or from marijuana. Hemp-derived CBD still contains trace amounts of THC, while marijuana-derived CBD may contain more.
What Is THC?
Delta-9-tetrahydrocannabinol, or THC, is the main psychoactive ingredient in cannabis. According to the National Institute on Drug Abuse (NIDA), THC activates the brain’s reward system by signaling the release of the brain chemical dopamine.1 Dopamine is a neurotransmitter that plays an important role in mood and pleasure. By triggering a higher-than-normal release of dopamine, THC causes people to experience feelings of euphoria. THC is often administered by smoking marijuana, but it can also be found as an ingredient in capsules, edibles, and oils.
CBD vs. THC: Key Differences
THC and CBD have an effect on the endocannabinoid system, a system that plays an important role in maintaining homeostasis. Researchers are still working to understand the ins and outs of this complex system, but they do know that it is associated with processes including memory, appetite, sleep, mood, and fertility.
While THC and CBD share similarities, there are some key differences between the two compounds.
- Psychoactive (produces a high)
- Sourced from marijuana
- Non-psychoactive (does not produce a high)
- Typically sourced from hemp
CBD and THC affect different receptors in the brain. Because of this, CBD typically does not have psychoactive effects—in other words, it won’t cause you to get high.
THC, on the other hand, does have psychoactive effects. It is the compound that produces the high that people associate with marijuana.
Both CBD and THC have a chemical structure that is similar to the body’s natural endocannabinoids. Endocannabinoids are neurotransmitters that act in the brain.
Neurotransmitters are chemical messengers that relay signals between nerve cells in the body. They play an important role in a wide range of functions including sleep, pain, appetite, mood, and the immune system.
CBD and THC have the same molecular structure, but there are differences in how these molecules are arranged that are responsible for the differing effects they have. By mimicking endocannabinoids, they bind with receptors and cause different effects in the body.
While CBD can come from either hemp or marijuana, it is often derived from hemp in order to avoid the addition of larger amounts of THC. THC, on the other hand, is derived from marijuana.
CBD that comes from marijuana may contain more THC, which may not be ideal for people who are trying to avoid THC. Some CBD products that are produced from cannabis, for example, may contain more THC than the label suggests.
Potential Benefits of CBD and THC
While research on the potential health benefits of THC, CBD, and other cannabinoids is still in the early stages, there is evidence that these substances may be helpful for conditions including:2
- Symptoms of HIV/AIDS
- Opioid dependence
- Irritable bowel syndrome (IBS)
- Inflammatory bowel syndrome (IBD)
- Multiple sclerosis
- Sleep difficulties
- Movement disorders
While CBD and THC often have similar effects and are often used to treat many of the same ailments, there are some differences.
CBD is often used to alleviate symptoms associated with:
THC, which may be administered as medical marijuana, may be used to alleviate symptoms of a number of conditions. It may be helpful for conditions such as:
- Nausea; it may be helpful for alleviated nausea caused by cancer treatment
- Pain associated with conditions such as arthritis, fibromyalgia, and migraine headaches
- Poor appetite; including appetite problems caused by cancer treatment
While cannabis itself has not been FDA approved to treat any condition, there are a few drugs approved by the U.S. Food and Drug Administration (FDA) that contain CBD or THC.2
- Epidiolex contains CBD and has been approved to treat seizures associated with two severe types of epilepsy—Dravet syndrome and Lennox-Gastaut syndrome
- Marinol and Syndros are drugs that contain dronabinol, a synthetic THC. These drugs are used to treat nausea and vomiting caused by chemotherapy during cancer treatment.
- Cesamet contains nabilone, a synthetic substance that is similar to THC. This drug is used to treat weight loss and appetite problems associated with chemotherapy and HIV/AIDS.
Side Effects of CBD and THC
Some research suggests that CBD and THC are generally safe and result in few side effects.
However, while these substances appear safe, that does not necessarily mean that you won’t experience some unwanted effects. Some adverse effects that have been reported include:
- Changes in mood and appetite
- Feelings of anxiety or other mood changes
- Nausea and dizziness
THC use may also result in unpleasant side effects such as increased heart rate, dry mouth, and memory loss.
Marijuana itself can have a number of short-term and long-term adverse effects, including impaired short-term memory , altered judgment, and impaired coordination. Research also suggests that marijuana can alter brain development and may lead to cognitive impairment.3
NIDA also notes that THC alters how the hippocampus and orbitofrontal cortex function. These areas of the brain are important in the formation of new memories and the ability to shift attention from one thing to the next. This not only affects a person’s ability to learn and form new memories, but it also makes it difficult for people to perform difficult tasks.1
Legality of CBD and THC
When choosing products containing CBD or THC, it is also important to consider their legality. Both marijuana and THC are included in the U.S. Controlled Substances Act, which means that they are not legal under federal law. As of July 2020, 33 states and Washington, D.C. have enacted policies allowing medical marijuana and products containing THC to be prescribed by a doctor. Some states also allow recreational use of marijuana and THC-containing products.
Although CBD in certain forms is legal in most states, the specifics of the legality of any THC or CBD product can vary from one state to the next. Several states have also approved the use of marijuana and THC for recreational purposes.
Because the laws regarding the use of cannabis and cannabis products are rapidly changing, you should always check your state’s laws before using products containing CBD or THC.
How to Take CBD and THC
Both THC and CBD can be consumed in a number of different forms. THC may be consumed as marijuana by smoking, but a number of other cannabis products are also available including:
- Vape products
- Edibles including gummies and chocolates
- Beverages containing marijuana oil
Like THC, CBD can also be consumed in a number of different forms. CBD oils can be formulated for vaping, although there have been recent concerns about the health dangers posed by vaping.
It can also be added to lotions and salves to apply to skin. It is important to note that the effects of these topical products will be localized since they are not being ingested.
CBD can also be taken orally as a tincture, oil, capsule, or spray. Edible CBD products are also popular and include gummies, candies, and beverages.
When choosing CBD products, it is also important to consider its formulation. Isolate products contain only CBD. Broad-spectrum products contain other cannabinoids with the exception of THC, while full-spectrum CBD products contain CBD, THC, and other cannabinoids.
Which One Should You Take?
The product you choose may depend on the effects you are trying to achieve. If you are trying to reduce stress or sleep better, for example, CBD may provide benefits without the negative side effects associated with THC. THC might be a better choice for symptoms or conditions for which the substance has demonstrated benefits, such as tremors or poor appetite.
Some research suggests that the potential therapeutic effects of THC and CBD tend to be greater when the two cannabinoids are taken together at the same time.4 This phenomenon is known as the entourage effect.
Taking CBD along with THC has also been shown to help reduce some of the unwanted effects that THC may have. For example, one study suggests that CBD may potentially reduce some of the negative cognitive effects of regular cannabis use.5 For example, people who use cannabis, particularly when it has high THC levels, may have a greater risk of experiencing psychiatric symptoms such as paranoia, anxiety, and psychosis. Studies have found, however, that CBD may help mitigate these effects.
One study found that CBD helped block some of the potential psychiatric effects of THC.6 The authors of the study suggest that such findings have important implications for the use of cannabis products. People who are prone to unwanted side effects, for example, may be able to still gain the potential health benefits by sticking to products that are low in THC and higher in CBD content.
It is also important to remember that CBD and THC work in a number of different areas of the brain and researchers do not yet fully understand the effects that these cannabinoids have, either alone or in conjunction with one another.
Some evidence suggests that the combined effects of CBD and THC may be dependent on dose. A 2019 study, for example, found that low doses of CBD actually played a role in amplifying the psychoactive effects of THC, while high doses of CBD reduced THC’s effects.7
Drug Testing CBD or THC
Because THC is the main psychoactive substance in marijuana, it can be detected on most standard drug tests. CBD may be detectable as well, but many drug tests are not designed to look for cannabidiol.
However, many CBD products do contain trace amounts of THC. While these amounts are small, they may still be detectable if you are consuming large quantities of CBD or if the products you are using contain more THC than the packaging label claims.
Research has found, for example, that as many as 70% of CBD products are mislabeled and contain significantly more THC than labels suggest.8 Because of the lack of regulation of these products, it is difficult to know exactly how much THC you are actually getting.
Both THC and CBD are stored in body fat, which means that both can potentially be detected on drug tests for some time after you have stopped using them.
Before You Take CBD or THC
THC and CBD may also have an effect on some health conditions and can interact with certain medications, so you should always use caution before taking these products. These substances might impact how medications are metabolized by your body. They can also heighten feelings of anxiety in some cases.
Before choosing a THC or CBD product, it is important to check your state laws to ensure that these products are legal where you live. Federal law mandates that hemp-derived CBD products should contain less than 0.3% THC, but even those trace amounts are still illegal in some states.
A Word From Verywell
Both THC and CBD may have a number of benefits, but you should always talk to your doctor first before you try any products containing these cannabinoids. Both CBD and THC hold promise for alleviating symptoms and even treating some medical and mental health conditions, but research in this area is still relatively new and further investigation is needed.