Lamotrigine-13C3 is an isotopically labeled form of Lamotrigine . Lamotrigine functions as an inhibitor of voltage gated sodium channels of presynaptic neurons. Studies indicate that Lamotrigine blocked sustained repetitive firing of neurons in a dose dependent manner in cultured mouse spinal cords. These studies indicate that Lamotrigine is effective at suppressing the release of glutamate and aspartate, but have no effect on acetylcholine and GABA release. Lamotrigine is inactivated by liver microsomes, via hepatic glucuronidation. It is believed that Lamotrigine modulates the fast voltage-dependent sodium currents in a manner similar to phenytoin and carbamazepine . Furthermore, Lamotrigine displays a small frequency dependent inhibition of depolarized potentials that result from sodium currents. Lamotrigine-13C3 can be beneficial in research due to its isotopic label, which makes identification of the molecule easier|in situ|.