Doctor’s Advice

by Charles E. Crutchfield III, MD
Wednesday, May 1, 2019

CBD oil has become wildly popular, But is it safe and effective?

Everywhere you look, from bath oils to soft drinks to skin creams to coffee bars, you see the new hot product, cannabidiol (CBD) — a member of the cannabinoid family of molecules. It is an oil found in marijuana and plants closely related to marijuana, such as hemp.

Although CBD has been around since the 1940s, CBD’s popularity has dramatically increased along with the legalization of medical and recreational marijuana across the United States. CBD oil is extracted from the buds and flowers of marijuana and related plants. But unlike a different psychoactive marijuana derivative oil, tetrahydrocannabinol (THC), CBD does not produce a “high” or intoxicated feeling.

CBD does have medicinal benefits, however. There are over 100 different cannabinoids found in cannabis plants. THC and CBD are the most commonly studied.

Proponents of CBD claim that it can treat a variety of conditions, including seizures, pain, anxiety, inflammation, insomnia, acne and other skin diseases, and even some forms of cancer. Experts are not quite as enthusiastic because solid scientific research has not verified most of these claims, yet.

That has not stopped marketers and producers. As mentioned earlier, CBD-containing products are found everywhere from bath and body stores to the local coffee shop. In fact, many malls now have CBD stores that sell a wide variety of products all containing CBD oil touted to treat a wide variety of health concerns. Search “CBD oil” on Amazon.com and well over 1,000 products are displayed!

Three types of cannabinoids

1. Phytocannabinoids: These are found in plants like marijuana and hemp.

2. Endocannabinoids: These are found in the human body, discovered as a result of studying phytocannabinoids. They are derivatives of a chemical called arachidonic acid. Many tissues and organs contain receptors for endocannabinoids.

It is known that endocannabinoids are released by human tissues in times of pain and inflammation. It is well documented that receptors for endocannabinoids are located throughout the human body, including skin cells, the nervous system and brain.

Endocannabinoids in the skin can regulate cell growth. The regulation of cell growth can also be used in cancer treatments. The endocannabinoids in the nervous system and brain may affect thinking and understanding, memory, body movements and pain control.

3. Synthetic cannabinoids: These are man-made cannabinoids used for research purposes and in some currently available products. They may eventually be employed in pharmacologic preparations and drug treatments used for cannabinoid-responsive conditions.

Three questions concerning CBD: safety, legality and effectiveness

1. Is it safe? Unfortunately, most CBD is being produced without regulation. As a result, the purity and quality can vary greatly.

In a recent study, 70 percent of online products evaluated contained a different amount of CBD than listed on the label. Most products examined had less CBD, but some had more. Also, about 21 percent of CBD-containing products had measurable amounts of THC. This derivative can cause anxiety — the very thing CBD is reported to calm.

Additionally, only about 20 percent of CBD gets absorbed when ingested orally, so the quality and purity of CBD products are critical for their effectiveness.

Some studies have shown that CBD can have adverse effects on the liver. This seems to be the case in up to 10 percent of all people. Other studies need to be done to see how CBD affects a person if the person consuming CBD is taking other medications. This is extremely important.

In general, there are relatively few side effects. So, the downside in using CBD-containing products is relatively low, but liver and other possible drug interactions must be considered.

2. Is it legal? This is really a grey and ever-changing area.

It appears to be legal in the 30+ states where medical marijuana is legal, but the overall national legal status has not yet been challenged, and the FDA has taken a very quiet and conservative stance.

Recently, a farm bill was proposed and is expected to pass that will make hemp-derived CBD legal. Keep in mind that just because something is legal does not mean that it is FDA-approved to treat anything or everything that is printed on the label.

3. Is it effective? There are CBD receptors in our bodies. In the presence of bound CBD, our bodies can produce physiologic responses. In fact, CBD is FDA-approved to treat certain epileptic seizures in children.

As for other health claims, much more research, especially on humans rather than animals, needs to be done. Unfortunately, due to lack of regulation, manufacturers of products that contain CBD can print just about any health claim they want on the product label, and buyers, desiring a relatively inexpensive, natural treatment, may just believe it.

There is emerging research that CBD may be useful in treating anxiety, and there are countless anecdotal reports that it helps muscle aches, joint pain, depression, psychiatric conditions and insomnia. The number of human trials for other diseases is small but promising.

In fact, CBD’s use as an anti-inflammatory may be the next area for future FDA investigation and approval. As mentioned, many cells in our bodies have CBD receptors, so it stands to reason that CBD can have physiologic effects in humans, such as on pain, inflammation, anxiety and sleep.

Unfortunately, due to the murky legal status of CBD, research to uncover these physiologic responses has been sparse. As the new farm bill clears, legality issues over research should move forward at a much faster pace. Additionally, the best method of CBD delivery (oral, topical or inhaled) should be studied for the best treatment results.

Use with guidance

CBD is a promising product for a variety of challenging medical conditions, but more research needs to be done. If a patient is considering the use of CBD when other tried and true treatments are not working, advise them not to just buy something off the shelf because the label says it will help him or her.

I would strongly suggest patients use CBD-containing products with the guidance and care of a physician knowledgeable about and familiar with CBD-containing products. The future appears bright for CBD-containing products, but its ultimate success will depend on the production of high-quality products with safe, proven and approved results.


Charles E. Crutchfield III, MD is a board-certified dermatologist and clinical professor of dermatology at the University of Minnesota Medical School. He also has a private practice in Eagan, Minnesota. He received his medical degree and master’s degree in molecular biology and genomics from the Mayo Clinic. He has been selected as one of the top 10 dermatologists in the United States by Black Enterprise magazine. Dr. Crutchfield was recognized by Minnesota Physician Magazine as one of the 100 Most Influential Healthcare Leaders in Minnesota. He is the team dermatologist for the Minnesota Twins, Vikings, Timberwolves, Wild and Lynx. Dr. Crutchfield is also an active member of both the American and National Medical Associations, and president of the Minnesota Association of Black Physicians.