How does CBD reduce seizures — what are the mechanisms?

CBD's anticonvulsant mechanisms are distinct from its anxiolytic effects and involve multiple molecular targets: (1) GPR55 antagonism — GPR55 is a putative cannabinoid receptor whose activation promotes neuronal excitability; CBD blocks it. (2) TRPV1 desensitization — reduces neuronal hyperexcitability. (3) Voltage-gated sodium channel modulation — CBD inhibits persistent sodium currents that drive repetitive firing. (4) Adenosine reuptake inhibition — increases extracellular adenosine, which has anticonvulsant effects via A1 receptors. (5) Modulation of intracellular calcium signaling. Notably, CB1 receptor agonism does not appear to be the primary anticonvulsant mechanism, which is why CBD works without psychoactive effects. The relative contribution of each mechanism varies by seizure type.