The good news is that higher-quality randomized clinical trials that examine the effectiveness of CBD oil for epilepsy are underway (some have even been completed), and the results should be published sometime this year.
In the meantime, there are a few things to keep in mind if you or your child suffers from intractable seizures and you’re considering trying cannabis oil.
First is that, as we’ve written before, medical marijuana (or cannabis) products are not subject to the same regulations as FDA-approved drugs. Even items sold through a dispensary or a mail-order service may be mislabled or contaminated.
Second, as noted above, even with design flaws that might have made CBD appear more effective than it really is, the available studies found that for most patients the drug did not work better than existing anti-epilepsy medication in treatment-resistant patients. That is, it reduced seizures by only a small amount in most patients.
Third is the available evidence on side effects: In the best-done study, 79 percent of participants reported adverse events from cannabis oil, including diarrhea and fatigue, but only 3 percent of them dropped out of the study. That adverse event rate is not small; according to a letter in the journal Lancet Neurology, it’s higher than the side effect rate for other epilepsy drugs. But by most expert accounts, the low drop-out rate suggests cannabis oil is safe—for short term use, at least.
For longer-term use, there are some causes for concern—namely that studies suggest extended or chronic cannabis consumption can cause lasting harm to the developing brain; it’s at least possible that those harms might be as pronounced for CBD as they are for traditional forms of the drug.
Still, treatment-resistant epilepsy is a debilitating condition that can dramatically impede a person’s quality of life. In severe cases, it can be life-threatening.
So with those caveats in mind, the bottom line is this: If you live somewhere you can legally obtain CBD, are suffering from intractable seizures, and all other approved therapies have failed, you might want to try cannabis. But you should only do so under the supervision of your regular doctor.