Need to know: The science behind medical marijuana

On this week’s “TechKnow,” contributor Crystal Dilworth travels to Colorado to learn more about Charlotte’s Web, a cannabis derivative that’s being used to treat kids with severe forms of epilepsy. We go inside the dispensary’s labs to see how the drug is made, what’s in it and how it works.

Cannabis is a genus of flowering plant that includes a single species, Cannabis sativa. The plant is used for fibers and oil (hemp), and may be used for medicinal purposes and as a recreational drug.

Cannabinoids are the active compounds in cannabis. Each plant contains more than 60 chemically related active compounds.

THC, or tetrahydrocannabinol, is the most well-known cannabinoid. It’s the psychoactive component that causes the high experienced after smoking or ingesting pot.

CBD, or cannabidiol, is a non-psychoactive cannabinoid. CBD could potentially have a wider scope of medical applications than THC or other cannabinoids. While not widely recognized by the medical community, CBD is integral to the medical marijuana movement, as it is purported to contain antimicrobial, antioxidant, neuroprotective and anti-epileptic properties.

The earliest research on the medical effects of CBD showed that the compound had anticonvulsive effects on patients with epilepsy. Later studies also demonstrated that CBD-rich marijuana did not seem to cause the same short-term memory loss seen in high-THC strains, but a lack of further clinical trials left most skeptical about the compound’s healing powers.

Jesse Stanley and his brothers began growing marijuana in 2008 after Colorado passed medical-marijuana laws. Their earliest efforts were focused on pain management and cancer treatments using THC, but when they began learning about the purported health benefits of CBD, they began breeding specifically to maximize CBD content in their plants. “We had a plant that was already fairly high, so we decided, why don't we try to make it higher? The studies that we had read (said that CBD) helped stopped the metastasizing of cancer, which is really important for us.”

The high-CBD plants were otherwise unusable — except for very specific medical treatments. “People commonly call it ‘the hippie’s disappointment,’” Jesse Stanley says. “You could smoke it all day and you wouldn’t get high.”

After being approached by the mother of a young girl with severe epilepsy, the Stanley brothers began focusing on the anticonvulsive properties of CBD, creating concentrated solutions of high-CBD, low-THC strains in order to safely monitor dosages in underage patients.

The resulting concentration has been nicknamed Charlotte’s Web, after Charlotte Figi, the girl who went from having up to 300 grand mal seizures a month to being seizure-free after starting CBD treatments.

To extract the CBD for medical treatment, chemists at the Stanley brothers’ labs soak high-CBD marijuana in food-grade alcohol to break down and extract the cannabinoids. Then the solution is heated in a rotary evaporator to remove the alcohol, leaving behind a high-CBD concentrate that is diluted with olive oil to stabilize the extract and make dosing easier.

Before and after the CBD concentrate is diluted, lab workers use a high-performance liquid chromatography (HPLC) machine to measure the ratio of CBD to THC in the concentrate. For medical-marijuana patients in search of pain management or appetite encouragement, a higher THC content would likely be desired. However, in the Charlotte’s Web strains, the Stanleys aim for a 30-to-1 ratio of CBD to THC, in order to achieve the anti-epileptic effects with a very small amount of the psychoactive component.  

To learn more about medical marijuana and Charlotte's Web, watch "TechKnow," 7:30ET/4:30PT.