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Facts / Conditions / Epilepsy

Cannabis & epilepsy

The one area where a cannabinoid crossed the full distance: anecdote → controlled trials → approved medicine.

What the evidence says
STRONG EVIDENCE

Pharmaceutical CBD is an approved anti-seizure medicine for severe childhood epilepsies

Epidiolex (purified CBD) won FDA and EMA approval for Dravet syndrome, Lennox-Gastaut syndrome and tuberous sclerosis complex after randomized placebo-controlled trials showed meaningful seizure reductions. This is the gold-standard path, completed.

CBD epilepsy trials — PubMed ↗
MODERATE EVIDENCE

Seizures drop by roughly a third to a half in responders — not to zero

Median convulsive-seizure reductions in the pivotal trials ran around 40–50% versus ~15–25% on placebo. Life-changing for many families, but "reduction", not "cure", is the honest frame.

Seizure reduction magnitude — PubMed ↗
STRONG EVIDENCE

Artisanal CBD oils are not interchangeable with the approved medicine

Trial results come from a standardized pharmaceutical preparation at 10–20 mg/kg/day. Market CBD products vary wildly in actual content and deliver far lower doses — families substituting them for Epidiolex are not running the same experiment.

CBD product content variability — PubMed ↗
MIXED / UNSETTLED

For adult focal epilepsies, the evidence has not landed yet

The completed trials concentrate on severe pediatric syndromes. Evidence for CBD in common adult focal epilepsy is promising but not yet approval-grade; trials are ongoing.

CBD adult focal epilepsy — PubMed ↗

The graded facts behind this page

This page is not medical advice.

Cannabis is not an approved treatment for epilepsy in most jurisdictions, and nothing here recommends using it. If epilepsy affects your life, bring this research — literally, these sources — to a physician and decide together. Laws differ by country and state; check CannabisLaws.ai before anything else.