Lacosamide in absence status epilepticus: Effective or ineffective?

We read with great interest the letter of Sodemann et al. on successful treatment of a patient with refractory absence status epilepticus (ASE) with lacosamide (LCM). In particular, Sodemann et al. reported the case of a 64-year-old male with juvenile absence epilepsy (he was on 400 mg/day lamotrigine, 400 mg/day topiramate and 2500 mg/day levetiracetam; plasma concentrations were not investigated) and an ASE treated with intravenous (IV) diazepam (10 mg, rapid but short lasting effect), IV levetiracetam (1000 mg, transient effect with ASE reoccurring after 3 h), and, finally, IV LCM (400 mg over a period of 30 min, complete recovery less than 2 h later). LCM was considered effective in this case. We recently reported the first episode of a treatment of ASE with IV lacosamide. The patient was already on large doses of levetiracetam (3000 mg/ day, plasma levetiracetam was 25 mg/L, range 10–37 mg/L) and valproate (2000 mg/day, plasma valproate was 87 mg/L, range 50– 100 mg/L), and had only a partial response to IV 20 mg diazepam. Unfortunately 400 mg of IV LCM was not effective (plasma LCM after infusion was 8.2 mg/L, range 1–10 mg/L) in the termination of the status epilepticus (after 24 h ASE spontaneously resolved).