ABCG2 and Lennox-Gastaut syndrome: Lamotrigine, an ASM sometimes prescribed in LGS and/or DS, is a P‐gp and a BCRP substrate, but the ASMs phenytoin, phenobarbital, carbamazepine, valproate, topiramate, and levetiracetam did not show substrate capacity for P‐gp and BCRP.50