What is CBD?

 Cannabidiol (CBD) is a non-psychoactive constituent of the plant Cannabis sativa – the two best known forms of which are marijuana and hemp.

Over 80 different chemicals, known as cannabinoids, have been identified from Cannabis sativa, of which delta-9-tetrahydrocannabinol (THC) is the major psychoactive compound.

CBD makes up around 40% of cannabis extracts. Although it is typically derived from marijuana or hemp, these products may contain traces of THC of other impurities.

This is not at all uncommon with CBD products. The Doctors of Pharmacology (PharmDs) at NaturalMedicines^TM (formerly Natural Medicines Comprehensive Database) warn, “Various commercially available cannabidiol dietary supplements have been shown to be contaminated with THC or synthetic cannabinoids.”

Fortunately, CBD can also be derived from other sources such as orange peels through a process that produces CBD with no THC or other impurities.

How popular is CBD and for what conditions do people use CBD?

CBD is growing wildly in popularity. The market size is soaring and could reach $1.3 billion in the U.S. by 2024.

The New York Times reports, “We are bombarded by a dizzying variety of CBD-infused products: beers, gummies, chocolates, and marshmallows; lotions to rub on aching joints; oils to swallow … Even CVS and Walgreens have announced plans to sell CBD products in certain states.”

The Times adds, “Many of these products are vague about what exactly CBD can do. … Yet promises abound on the Internet, where numerous articles and testimonials suggest that CBD can effectively treat not just epilepsy but also anxiety, pain, sleeplessness, Crohn’s disease, arthritis, and even anger.”

But has CBD been shown to be effective for anything?

The experts at NaturalMedicines^TM have concluded that there is insufficient reliable evidence to rate CBD as effective for a wide variety of indications – including anxiety, athletic performance, cancer, cognitive function, COVID-19, Crohn disease, diabetes, fibromyalgia, hypertension, insomnia, IBS, neuropathy, obesity, pain (acute or chronic), PTSD, rheumatoid arthritis, TMD, or for many other disorders for which it has been studied.

ConsumerLab.com notes, “Preliminary evidence suggests [CBD] may help with anxiety, schizophrenia, and other conditions. However, most of these effects have involved large doses of CBD – hundreds of milligrams per day, which is more than in many marketed CBD supplements and products. CBD applied to the skin (such as CBD creams, gels, and lotions) may modestly reduce some forms of pain and might promote hair regrowth).”

Has CBD been proven to work for anything?

There is one condition in which CBD has been proven effective: it’s a specific prescription cannabidiol product, Epidiolex®, which is FDA-approved for use in several forms of epilepsy, including Lennox-Gastaut Syndrome, Dravet Syndrome, and Tuberous Sclerosis Complex.

However, it is unclear if other CBD products are beneficial for these conditions. And Epidiolex is very expensive. Drugs.com quotes a cost “of around $1000 for a supply of 60 milliliters.” No wonder people wanting to try CBD choose over the counter products. But this can be risky.

What side effects does CBD have?

 NaturalMedicines^TM rates CBD as “possibly safe” when used orally and appropriately in adults; however, they do not give CBD their “probably safe” or “safe” rating.

They write that “CBD doses up to 200 mg daily have been used with apparent safety for up to 13 weeks, while higher doses of 700 mg daily for up to 6 weeks and 1200 mg daily for up to 4 weeks have also been used with apparent safety” concluding that oral CBD “seems to be well tolerated.”

But like every prescription or over the counter medicine, there are potential common adverse effects.

Prescription CBD causes sleepiness in up to 30% of patients and diarrhea in up to 24%.

It can also cause decreased appetite, drowsiness, dry mouth, fatigue, fever, and vomiting. The higher the dose, the more likely are side effects.

Fortunately, serious adverse effects, such as hepatitis, respiratory depression, and pneumonia, have been rare.

How do I choose a CBD to purchase if I want to try it?

In 2015, the FDA reported it found that many CBD-labeled products contained very little CBD.

Two years later, another study published in JAMA found that in eighty-four CBD products sold online, 43 (51%) had significantly more CBD than advertised, and 26 (31%) had significantly less. Also, 18 of the 84 products (21%) contained THC, with no THC listed on the label.

Tests of CBD oil products purchased at stores in Kentucky and online in 2021 found THC present in 5 of 21 (24%) products labeled as “THC-Free.” Among all 80 products tested, 51 (64%) contained THC at levels that could potentially cause people to test positive for marijuana.

A 2022 analysis from LeafReport (tinyurl.com/mwx3kfum) analyzed 4,384 products made by 188 different CBD brands. The results were discouraging:

• 20% of brands do not test their products for pesticides, heavy metals, or microbes (28% did not test for pesticides, 26% did not test for heavy metals, and 24% did not test for microbes).
• In fact, only 7% of the brands tested for all 3 contaminants.
• Only 42% of brands test the potency of almost all their products and only 12% of brands had all their products test within 10% of the stated potency with 88% of brands having at least one product that tested outside the acceptable potency variance.

What’s a consumer to do?

According to LeafReport, “Third-party lab testing is the only tool at a consumer’s disposal to determine the safety and purity of a CBD product they are considering using.” They add, “It is more important than ever before to choose your CBD products with an abundance of caution.”

My favorite independent testing lab is ConsumerLab.com. In their August 2026 CBD report, they reported finding, “CBD in all of the [tested] products (ranging from 2.5 mg to 51.3 mg per serving) but the cost to obtain an equal amount of CBD from each product ranged more than 10-fold, from just 24 cents to $2.67 per 10 mg.

Interestingly, there were many more good, lower cost products available on the market than CL found in its 2018 review. Levels of THC also tended to be much lower, with THC not detectable in most products.”

Based on quality and value, ConsumerLab selected several Top Picks for oral and topical use – as well as a Top Pick for pets (tinyurl.com/54hbab9j).

Other cautions and warnings

ConsumerLab.com also advises, “Look for CBD products that list the amount of CBD or cannabidiol per serving, and don’t confuse that with the amount per entire bottle. If a product lists only ‘cannabinoids’ it may contain some CBD, but you won’t know how much.

“Products may still have significant amounts of CBD if they list ‘hemp extract’ as an ingredient, but don’t expect much CBD if ‘hemp oil’ is the only ingredient. Hemp extracts are more likely to contain a range of cannabinoids in addition to CBD (although it’s not clear if this provides added benefit) … If you want to avoid THC, look for products [that] had no detectable THC in our tests. Note that CBD does not appear to be converted to THC in the body.”

“Warning letters from the FDA in November 2022 indicated that CBD is not permitted to be sold in forms that resemble conventional foods, such as gummies, tea, cookies, lollipops, fruit snacks, hard candies, and pet treats, emphasizing that CBD is not approved for use as a food additive, and expressing particular concern that such forms may appeal to children.”

Many states now have medical marijuana laws that permit products with CBD to be sold by approved dispensaries and used for medical purposes recommended by a healthcare professional.

In addition, some states without medical marijuana laws allow products that are high in CBD (at least 5%, 10%, or 15% CBD) and low in THC (typically less than 0.3% to 0.9%) to be used for specific medical purposes as approved or recommended by a healthcare professional (see a list of states on ProCon.org).

One practical note for readers who own or buy firearms. The federal firearms purchase form (ATF Form 4473) asks whether you are an unlawful user of marijuana or any other controlled substance. Hemp-derived CBD with less than 0.3 percent THC is legal under federal law, so using it does not make you an “unlawful user,” and you can answer that question truthfully with a “no.” Full-spectrum products that contain meaningful amounts of THC are a different story, and I address that in Part 2.

The bottom line about CBD

Buyer beware.

Discuss taking CBD with your family physician and your pharmacist.

Be aware that CBD may interact with quite a number of prescription, over the counter, or other natural (herb or supplement) medications.

There are any number of medication interaction checking sites on the Internet. If you decide to try CBD, start at very low doses, and increase the dose very slowly.

Finally, CBD supplements can contain enough THC to cause a positive drug test for marijuana and some branches of the U.S. military forbid the use of any hemp-based products.

This post was accurate to the best of my knowledge when written. Cannabis laws and regulations are changing month to month. Nothing here is legal advice, and any decision to use cannabis medically should be made with your personal physician and pharmacist.

A PDF OF THIS POST IS HERE: Medical Marijuana – Part 1 – What You Should Know About CBD-1

The Series

• 10/9/26 – Part 1: Medical Marijuana – What is CBD?
• 10/16/26 – Part 2: Medical Marijuana – What It Is and what is the Law?
• 10/23/26 – Part 3: Medical Marijuana – What is the evidence and what are the harms?
• 10/30/26 – Part 4: Medical Marijuana – Should a Christian Use It?
• 11/6/26 – Part 5: Medical Marijuana – A note for my fellow Christian physicians

Walt Larimore, MD, has been called one of America’s best known family physicians and has been named in the “Guide to America’s Top Family Doctors,” “The Best Doctors in America,” “Who’s Who in Medicine and Healthcare,” and “Who’s Who in America.” He’s a former Vice President and Physician in Residence at Focus on the Family and the American Life League has named him a “Rock-Solid Pro-Life” awardee. He’s also an award-winning medical journalist and the best-selling author of over 40 books. He and his childhood sweetheart and wife of nearly 50 years, Barb, have two adult children and reside in Colorado Springs. You can find Doctor Walt’s health blog at www.DrWalt.com and follow him on Facebook at “DrWalt.com”.

© Copyright WLL, INC. 2026. This blog provides healthcare tips and advice that you can trust about a wide variety of general health information only and is not intended to be a substitute for professional medical advice, diagnosis, or treatment from your regular physician. If you are concerned about your health, take what you learn from this blog and meet with your personal doctor to discuss your concerns.