Debunking Dispensary CBD

Epilepsy patients using dispensary cannabidiol (CBD) showed no clinical benefit and did not reach therapeutic levels of CBD in the blood serum, according to research published by Taylor Elliott, BS, in Child Neurology Open. Elliott published this research while he was a Rhodes College Summer Plus Fellow with Le Bonheur Children’s Hospital’s Neuroscience Institute. He is now a medical student at The University of Tennessee Health Science Center.

Despite the U.S. Food and Drug Administration (FDA) approval of Epidiolex, a liquid CBD medication, patients continue to supplement prescription treatments with dispensary CBD. Le Bonheur neurologists sometimes prescribe Epidiolex for specific epilepsies that have been proven in clinical trials to benefit from the medication.

This study found that patients who take dispensary CBD in addition to prescribed antiseizure medications had CBD serum levels below the therapeutic range — and some had small levels of tetrahydrocannabinol (THC).

“Even before the FDA approved the prescription formulation of CBD, many epilepsy patients obtained internet-based dispensary CBD products to supplement their prescribed treatment regimen,” said Elliott. “We hope that awareness of assayed CBD serum levels in patients on these non-prescription CBD products will better help inform patient care.”

Prescription CBD is distinct from other antiseizure medications, which primarily affect sodium and potassium channels. CBD acts on multiple targets: It creates an inhibitory signal by increasing adenosine uptake into neurons, and it decreases intracellular calcium release that
precedes excitatory neuronal activity. Prescription CBD is a purified plant-based product that lacks the psychoactive properties of THC and has been proven to be an effective antiseizure medication.

Researchers conducted a retrospective chart review of patients within the Comprehensive Epilepsy Program at Le Bonheur’s Neuroscience Institute who reported taking non-prescription CBD. A total of 18 patients were identified between 2 and 32 years old. Patients had little to no consistency in dosage and serum levels and used CBD from 12 different dispensaries.

The therapeutic range of CBD serum is greater than 100-150 ng/mL. CBD serum levels of patients in the study were as follows: 

• Six patients had serum levels below the lab reporting level of 1 ng/mL.
• Children (2 to 11 years) had an average serum concentration of 9.4 µg/mL.
• Adolescents (12 to 17 years) had an average serum concentration of 7.4 µg/mL.
• Adults (older than 18 years) had an average serum concentration of 14.21 µg/mL. All adults were long-term patients who began epilepsy treatment at Le Bonheur in early childhood.

No side effects were reported, but minute levels of THC were found in three patients and moderate levels of THC were found in one patient. 

“Dispensary CBD failed to reach effective therapeutic levels in all patients. This minimal concentration suggests that there is no benefit in adding these products to a treatment regimen,” said Elliott.

The results of the study demonstrate the lack of regulation in the CBD dispensary industry, especially with the small amounts of THC found in some patients. Anecdotal reports of the clinical effectiveness of CBD are likely a result of prescription antiseizure medication and not dispensary CBD, says Elliott.

“Our study supports the clinical practice of obtaining serum levels of CBD and THC in all patients treated with internet-based dispensary products,” said Elliott. “We found that all 18 of our patients had no therapeutic level and would potentially benefit from switching to prescription CBD.”

Elliott T, et al. Dispensary Cannabidiol (CBD): Nothing to Worry About!. Child Neurol Open. 2023;10:2329048X231169395.