High-ratio CBD effective for seizure control in epilepsy, quality control a challenge

LAS VEGAS — Cannabinoids have been shown to effectively control seizures across the epilepsy spectrum; however, quality control of products remains a challenge, according to a presenter at BRAINWeek 2022.

“We’re not really helped by the medical establishment, or government, or anybody else,” Jay Salpekar, MD, associate professor of psychiatry and neurology at Johns Hopkins University School of Medicine and director of neuropsychiatry in the epilepsy program at Kennedy Krieger Institute, said during the presentation. “That’s the thing that rang true with parents, with their kids and epilepsies, things stopped working. They’ve had to try something different.”

Another obstacle, Salpekar said, is that there is an overrepresentation of psychiatric comorbidities in epilepsy, with 10% to 33% of patients reporting symptoms of anxiety and depression. Research also has shown that epilepsy is linked to a fivefold increase in suicidal ideation.

Salpekar noted that because some anticonvulsants improve behavior as well as seizures, it has been suggested that cannabinoids may do the same. This requires an understanding of the endocannabinoid system in the brain and how cannabinoids affect it, he said.

Within the clinical spectrum, there are few treatments available — CBD, THC and synthetic THC among them — with available research on CBD dating back to only 1980. In addition, pharmaceutical-grade CBD is only approved for seizure symptoms and not the root cause of disease, Salpekar said.

Physicians also should be mindful of interactions with other drugs and metabolic processes, along with considerations for the proper ratio of CBD to THC in the product prescribed.

Salpekar noted that the ratio of CBD to THC in pharmaceutical grade CBD is 50:1, which is optimal for seizure control. However, opinions vary on the proper ratio to address seizures, mood disorders and anxiety.

Also of note, Salpekar said, is the way the CBD is administered, with ingested product having an onset of 30 minutes to 2 hours and a duration of 2 to 5 hours, while sublingual and inhaled forms have more immediate impact and potentially less duration.

Clinical treatment with CBD, he continued, is also dependent upon how terpenes — unsaturated hydrocarbons found in the essential oils of plants, especially conifers and citrus trees — affect different receptors. For example, lavender may work best for anxiety, and limonene may help lessen depressive symptoms.

However, according to Salpekar, quality control of products remains the greatest challenge.

“We know high-ratio CBD is effective for seizure control,” he said. “We have pretty good data on that. It may not work for all types of seizures, and it may not work all the time. But we still don’t know what the dosing is. It demands a little more thought process to really nail it down.”