Stiripentol-d9 is intended for use as an internal standard for the quantification of stiripentol by GC- or LC-MS. Stiripentol is a third-generation antiepileptic compound.1 It is a positive allosteric modulator of GABAA receptors, potentiating GABA-mediated activation to a greater extent in receptors expressing α3 subunits and to a lower extent in those containing β1 or ε subunits.2 It also inhibits GABA reuptake in vitro and increases the release of GABA in neonatal rat hippocampal slices.1,3 Stiripentol (500 μM) inhibits lactate dehydrogenase (LDH), blocking both lactate-to-pyruvate and pyruvate-to-lactate conversions by human LDH1 and LDH5.4 Formulations containing stiripentol have been used in the adjunctive treatment of seizures associated with Dravet syndrome.

|1. Luszczki, J.J. Third-generation antiepileptic drugs: Mechanisms of action, pharmacokinetics and interactions. Pharmacol. Rep. 61(2), 197-216 (2009).|2. Fisher, J.L. The anti-convulsant stiripentol acts directly on the GABAA receptor as a positive allosteric modulator. Neuropharmacology 56(1), 190-197 (2009).|3. Quilichini, P.P., Chiron, C., Ben-Ari, Y., et al. Stiripentol, a putative antiepileptic drug, enhances the duration of opening of GABAA-receptor channels. Epilepsia 47(4), 704-716 (2006).|4. Sada, N., Lee, S., Katsu, T., et al. Targeting LDH enzymes with a stiripentol analog to treat epilepsy. Science 347(6228), 1362-1367 (2015).