Can Cannabis Be Used to Treat Epilepsy?

Yes, a purified prescription form of cannabidiol can reduce seizures in certain epilepsy syndromes. That evidence does not mean that cannabis flower, THC products or retail CBD oils are established treatments for epilepsy generally. The diagnosis, formulation and medical monitoring matter.

What Is Approved for Epilepsy?

The current US Epidiolex prescribing information covers seizures associated with Lennox-Gastaut syndrome, Dravet syndrome and tuberous sclerosis complex in patients one year of age and older. Epidiolex is a prescription cannabidiol oral solution.

CBD does not produce the same high as THC. Its precise anticonvulsant mechanism in humans remains unknown; the label indicates that it does not appear to work through cannabinoid receptors. The endocannabinoid system is therefore not a complete explanation for its clinical effects.

What the Trials Actually Demonstrated

In a 2017 randomized Dravet syndrome trial, 120 children and young adults received cannabidiol or placebo alongside their existing antiseizure treatment. Median monthly convulsive seizures fell from 12.4 to 5.9 with cannabidiol, compared with 14.9 to 14.1 with placebo. Adverse effects occurred more often with cannabidiol. This demonstrated a reduction in seizures, not a universal cure or proof that existing medicines could be stopped.

A randomized trial in tuberous sclerosis complex also tested purified cannabidiol as an added treatment. The reduction in the seizure types assessed as the primary outcome was 48.6% in the 25 mg/kg/day group versus 26.5% with placebo. The higher experimental dose did not provide a greater reduction and had tolerability disadvantages. These are supervised research doses, not instructions for dosing a retail oil.

The trials support particular formulations and conditions. They should not be generalized to every seizure type or to products with different ingredients and cannabinoid concentrations.

Why Medical Supervision Is Necessary

Prescription CBD can cause diarrhea, reduced appetite, sleepiness and liver enzyme elevations. Its label requires liver blood tests before treatment and ongoing monitoring. Valproate increases the liver-risk concern; CBD can also increase exposure to clobazam’s active metabolite. The prescriber must review the full medication list and adjust treatment when needed.

Do not abruptly discontinue Epidiolex or other prescribed antiseizure treatment without medical direction. Sudden withdrawal can worsen seizure control. Follow the clinician’s dosing and monitoring plan rather than copying another patient’s regimen.

Keep a seizure diary that records seizure type, frequency, duration, possible triggers and treatment changes. Bring it to appointments along with details of side effects. Fewer seizures are valuable, but alertness, nutrition and day-to-day functioning also matter when deciding whether treatment is helping.

Retail Cannabis Is Not an Equivalent Substitute

The FDA distinguishes approved medicines from unapproved cannabis and CBD products. A bottle advertised for wellness has not necessarily been evaluated for seizure treatment, reliable dosing or interactions. A “CBD-rich” description does not establish equivalence to a prescription formulation.

If seizures remain uncontrolled, ask an epilepsy specialist about the diagnosis and the full range of treatment options. The World Health Organization notes that many people can become seizure-free with appropriate diagnosis and treatment, and surgery may benefit some people who respond poorly to medicines. Cannabis should not delay that assessment.

Have a Seizure Action Plan

CBD is not a substitute for prescribed rescue medicine or emergency care. Follow the individual’s seizure action plan and make sure caregivers know where rescue medication is kept and how to use it.

CDC seizure first-aid guidance recommends staying with the person, protecting them from injury and timing the seizure. Do not restrain them or put anything in their mouth. Turn them gently onto their side when they are lying down, and do not offer food or water until they are fully alert.

Call 911 if a seizure lasts longer than five minutes, another follows soon afterward, the person has trouble breathing or waking afterward, or an injury occurs. A first seizure or a seizure in water also requires emergency help. Use the local emergency number outside the United States.