A perspective on cannabinoids for treating epilepsy: Do they really change the landscape?

Area of Science:

• Neuroscience and Pharmacology
• Epilepsy Research
• Cannabis-Based Medicine

Background:

• Growing interest in cannabis-based medicinal products for epilepsy following the 2018 US licensing of cannabidiol (CBD) for specific seizure types.
• Existing unmet needs in epilepsy treatment drive exploration of alternative therapies.
• Both CBD and tetrahydrocannabinol (THC) have proposed multimodal mechanisms of action, extensively studied in animal models.

Purpose of the Study:

• To review current knowledge on cannabis-based medicinal products for epilepsy.
• To discuss implications for future research and clinical practice.
• To address the gap between scientific evidence and public perception regarding cannabis and epilepsy.

Main Methods:

• Review of existing scientific literature and controlled trials.
• Analysis of data on efficacy, adverse effects, and drug interactions of CBD and THC.
• Consideration of public interest versus clinical concerns regarding cannabis constituents.

Main Results:

• Pure CBD formulations demonstrated modest but significant improvements in motor seizures in controlled trials.
• Common adverse effects of CBD include diarrhea, somnolence, and reduced appetite; serious adverse events occur in up to 1 in 23 patients.
• Significant drug interactions exist, notably with valproate (hepatotoxicity risk) and clobazam (increased somnolence).

Conclusions:

• Clinicians express concerns regarding the risks of THC, particularly for epilepsy patients with existing mental health comorbidities.
• Artisanal cannabis preparations are not recommended due to inconsistent and unknown constituents.
• Continued education and high-quality research are crucial to mitigate risks and inform public, policymakers, and healthcare providers about the evidence for cannabis-based epilepsy treatments.