The exact mechanism by which oxcarbazepine exerts its anticonvulsant effect is unknown. It is known that the pharmacological activity of oxcarbazepine occurs primarily through its 10-monohydroxy metabolite (MHD). In vitro studies indicate an MHD-induced blockade of voltage-sensitive sodium channels, resulting in stabilization of hyperexcited neuronal membranes, inhibition of repetitive neuronal discharges, and diminution of propagation of synaptic impulses.

Oxcarbazepine is structurally a derivative of carbamazepine, adding an extra oxygen atom to the benzylcarboxamide group. This difference helps reduce the impact on the liver of metabolizing the drug, and also prevents the serious forms of anemia occasionally associated with carbamazepine. Aside from this reduction in side effects, it is thought to have the same mechanism as carbamazepine - sodium channel inhibition - and is generally used to treat the same conditions.

Oxcarbazepine is completely absorbed and extensively metabolized to its pharmacologically active 10-monohydroxy metabolite (MHD). MHD is metabolized further by conjugation with glucuronic acid.

Isolated cases of overdose with oxcarbazepine have been reported. The maximum dose taken was approximately 24, 000 mg. All patients recovered with symptomatic treatment.

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