SubEx

Manage seizures

7 findings · 2 substances · 5 well-evidenced

Two severe epilepsies and one pregnancy emergency hold every seizure finding: a prescription medicine cut seizures in randomised trials, and a hospital drip more than halved them. More of the medicine added side effects, not control.

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Findings

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OtherCBD cut seizures whether or not another epilepsy drug was on board

Splitting four trials by clobazam use, seizures halved in 29.1% on cannabidiol against 15.7% without it, and in 52.9% against 27.8% among those already taking clobazam.

★★★Well replicated — this finding’s sources average out to meta-analyses, systematic reviews or high-powered trials.Nobody was randomised to clobazam — patients arrived on it or not — so the two groups differ in ways beyond the drug. The response was much higher in the clobazam group in both arms, placebo included, which the authors flag rather than resolve. Only Dravet and Lennox-Gastaut trials are pooled.Click to keep this openManage seizuresCannabidiol (CBD)
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OtherMore CBD did not mean fewer seizures, only more diarrhoea

Cannabidiol beat placebo by 19.5 percentage points at 10mg/kg/day and 19.9 at 20mg/kg/day, while quitting for side effects rose from 1.66 to 6.89 times placebo.

★★★Well replicated — this finding’s sources average out to meta-analyses, systematic reviews or high-powered trials.One trial does not fit cleanly: in Lennox-Gastaut syndrome the 20mg/kg/day arm ran about five percentage points ahead of the 10mg/kg/day arm on drop seizures. No trial here powered its two active doses against each other, so every dose comparison is descriptive rather than a tested difference.Click to keep this openManage seizuresCannabidiol (CBD)
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PainSeparate CBD from THC and only the epilepsy result survives

Across 152 trials in 12,123 people, cannabidiol's only strongly graded benefit was epilepsy. The pain, spasticity and sleep effects credited to cannabinoids came from THC-containing ones.

★★★Well replicated — this finding’s sources average out to meta-analyses, systematic reviews or high-powered trials.Eighty-four separate comparisons across 23 conditions means some significant findings are expected by chance, and most were graded low or very low quality. The missing cannabidiol effect on pain is an absence of evidence inside these trials, not a tested null.Click to keep this openRelieve painCannabidiol (CBD)
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OtherChildren with Dravet syndrome went from 12.4 seizures a month to 5.9

On added cannabidiol at 20mg/kg/day, the median fell from 12.4 convulsive seizures a month to 5.9. On placebo it moved from 14.9 to 14.1.

★★★Well replicated — this finding’s sources average out to meta-analyses, systematic reviews or high-powered trials.The placebo groups improved too — 21.8% fewer drop seizures in Lennox-Gastaut. In Dravet, the share of patients whose seizures halved did not separate from placebo (43% against 27%), so the finding rests on the seizure count alone. Both trials were manufacturer-funded.Click to keep this openManage seizuresCannabidiol (CBD)
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Sexual & reproductiveThe hospital magnesium drip more than halved seizures in pregnancy

Magnesium sulphate given by drip to 10,141 women with pre-eclampsia more than halved eclamptic seizures and cut the mother's own risk of dying. Magnesium capsules are not this drug.

★★★Well replicated — this finding’s sources average out to meta-analyses, systematic reviews or high-powered trials.This is magnesium sulphate at monitored clinical doses through a vein; magnesium sold in capsules has never been shown to do anything for eclampsia risk. The trial ran across 33 countries with very different standards of care, so the background risk it was measured against varied from site to site. And the Cochrane review is built around this same trial, so the two are not independent of each other.Click to keep this openSupport a healthy pregnancyMagnesium
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OtherAdding CBD raised a clobazam by-product, not clobazam itself

In 20 patients already taking clobazam, adding cannabidiol at 20mg/kg/day left clobazam levels unchanged while its active breakdown product rose two- to three-fold.

★★☆Single study — solid evidence, such as one good trial or a large observational dataset, but not replicated at the top tier.Twenty people, run by the maker of the cannabidiol formulation, and built to measure blood levels rather than outcomes — it establishes the exposure change, not its consequences. The dose is a prescription epilepsy one; whether the same happens at consumer amounts was not tested.Click to keep this openManage seizuresCannabidiol (CBD)
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OtherPrescription CBD's liver signal was mostly about the drug alongside it

At 10 to 25mg/kg a day for severe epilepsy, liver enzymes above three times normal appeared in 30% on both valproate and clobazam, 21% on valproate alone, 4% on clobazam alone, 3% on neither.

★★☆Single study — solid evidence, such as one good trial or a large observational dataset, but not replicated at the top tier.These rates come from patients with severe epilepsy on cannabidiol at 10 to 25mg/kg/day, far above what consumers take. NIH's LiverTox reference gives 21% for the valproate-and-clobazam group where the label gives 30%, attributing its figure to extension studies rather than to these trials.Click to keep this openSupport liver healthCannabidiol (CBD)
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