Felbamate

Felbamate is an inhibitor of NMDA receptors and a modulator of GABA_A receptors that also has broad-spectrum inhibitory activity against excitatory amino acid receptors.^1,2,3 It binds to NMDA channels with dissociation constants of approximately 200, 110, and 55 µM in the resting, activated, and desensitized states, respectively, and inhibits NMDA currents in a use-dependent manner.¹ Felbamate is a positive modulator of α₁β₂γ_2S, α₁β₃γ_2S, α₂β₂γ_2S, and α₂β₃γ_2S subunit-containing GABA_A receptors expressed in X. laevis oocytes, with negative modulation of GABA_A receptors containing the subunits α₁β₁, α₁β₃γ_2L, α₄β₁γ_2S, α₄β₃γ_2S, and α₆β₁γ_2S.² It inhibits seizures induced by maximal electroshock, pentylenetetrazole (Item No. 18682), and picrotoxin (Item No. 20771) in mice (ED₅₀s = 16.3, 5.51, and 5.23 mg/kg, respectively). Formulations containing felbamate have been used in the treatment of severe refractory seizures.⁴

WARNING This product is not for human or veterinary use.

1. Kuo, C.-C., Lin, B.-J., Chang, H.-R., et al. Use-dependent inhibition of the N-methyl-D-aspartate currents by felbamate: a gating modifier with selective binding to the desensitized channels. Mol. Pharmacol. 65(2), 370-380 (2004).

2. Simeone, T.A., Otto, J.F., Wilcox, K.S., et al. Felbamate is a subunit selective modulator of recombinant γ-aminobutyric acid type A receptors expressed in Xenopus oocytes. Eur. J. Pharmacol. 552(1-3), 31-35 (2006).

3. Domenici, M.R., Sagratella, S., Ongini, E., et al. Felbamate displays in vitro antiepileptic effects as a broad spectrum excitatory amino acid receptor antagonist. Eur. J. Pharmacol. 271(2-3), 259-263 (1994).

4. Swinyard, E.A., Sofia, R.D., and Kupferberg, H.J. Comparative anticonvulsant activity and neurotoxicity of felbamate and four prototype antiepileptic drugs in mice and rats. Epilepsia 27(1), 27-34 (1986).