Lamotrigine-d₃is intended for use as an internal standard for the quantification of lamotrigine by GC- or LC-MS. Lamotrigine is an anticonvulsant.¹It inhibits voltage-gated sodium channels (Na_v) in HEK293 cells expressing recombinant human Na_v1.2, Na_v1.5, or Na_v1.8 (IC₅₀s = 10, 62, and 96 μM, respectively), as well as high voltage-activated calcium currents in isolated rat cortical neurons (IC₅₀= 12.3 µM), an effect that can be reversed by the N-type calcium channel blocker ω-conotoxin GVIA and P-type calcium channel blocker ω-agatoxin IVA .^1,2Lamotrigine protects against seizures induced by maximal electroshock (MES) in mice and rats (ED₅₀s = 10.1 and 7.4 µmol/kg, respectively).³It also decreases mechanical allodynia in a rat model of neuropathic pain induced by spinal nerve ligation (ED₅₀= 47 µmol/kg).¹Formulations containing lamotrigine have been used in the treatment of epilepsy and bipolar disorder.

1.Drizin, I., Gregg, R.J., Scanio, M.J., et al.Discovery of potent furan piperazine sodium channel blockers for treatment of neuropathic painBioorg. Med. Chem.16(12)6379-6386(2008) 2.Stefani, A., Spadoni, F., Siniscalchi, A., et al.Lamotrigine inhibits Ca2+ currents in cortical neurons: Functional implicationsEur. J. Pharmacol.307(1)113-116(1996) 3.Miller, A.A., Wheatley, P., Sawyer, D.A., et al.Pharmacological studies on lamotrigine, a novel potential antiepileptic drug: I. Anticonvulsant profile in mice and ratsEpilepsia27(5)483-489(1986)