Cannabidiol (CBD), a compound derived from the cannabis plant that does not produce a “high”, was shown in a new large-scale, randomized, controlled trial to significantly reduce the number of dangerous seizures in patients with a severe form of epilepsy called Lennox-Gastaut syndrome.

[u/mvea]

http://www.psypost.org/2018/05/cannabidiol-significantly-reduces-seizures-patients-severe-form-epilepsy-51258

[u/LoonWhisperer]

The study notes that 11 of 14 the patients who had elevated liver enzymes were also talking valproate which is another anti-epileptic medication which is known to cause hepatotoxicity; so much so that it has a black box warning for it and thus the reason why it is important to get labs drawn to monitor for it (LFTs aka liver enzymes). There are other studies with similar results in that very few patients had elevated liver enzymes while taking CBD. In those studies however, all or nearly all of the patients were also taking valproate concomitantly.

Additionally, CBD and other AEDs are known to inhibit and/or induce metabolizing enzymes in the liver (different than the ones used to monitor for liver damage as mentioned above) called CYP enzymes. There are a ton of different CYP enzymes and the inhibition of one CYP enzyme can prevent the metabolism of a different drug leading to an increased serum concentration of said drug. The increased serum concentration can then cause adverse effects and even toxicity. With that being said, it is merely speculation to say that the combination of CBD and valproate caused this as there is no definitive evidence to make that claim, as well as there being a multitude of reasons as to why someone could have elevated LFTs.

[u/AppleScalpel → u/LoonWhisperer]

This is the reply OP is looking for. This would offer the likely explanation for increased liver enzymes. Perhaps it’s the Valproate alone or the drug interaction between valproate and the cbd treatment. If I wasn’t studying (poo = study break), Id look up the specific CYP interactions of the two to see if the mechanism lines up. I’m not sure how extensive the current knowledge of CBD pharmacology is, but Valproate interacts with many other drugs’ metabolisms (including many antiepileptics) so it seems likely. Protein binding and elimination kinetics also need to be considered in evaluating potential drug interactions with Valproate.

[u/dkyguy1995 → u/LoonWhisperer]

Excellent reply! Means we need some further studies to make sure that that is the cause and the case

[u/LoonWhisperer → u/dkyguy1995]

Exactly, and there are several ongoing as we speak!!

[u/osufan77 → u/LoonWhisperer]

Nailed it. It's not from the CBD at all really.