Successful case of Lance-Adams syndrome treatment with early use of perampanel after targeted therapeutic hypothermia

Perampanel (PER), approved as an antiseizure medication in 2012, is a selective non-competitive antagonist of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors. PER is used as an add-on medication to treat partial-onset and primary generalized tonic-clonic seizures. In addition, positive effects have been reported in some patients with epileptic myoclonic convulsions in idiopathic systemic and progressive myoclonic epilepsy. We treated a male patient with post-hypoxic nonepileptic myoclonus (Lance-Adams syndrome) by adding PER to classic antiseizure medications after 10 days of targeted therapeutic hypothermia. Myoclonus movement, which showed no improvement with other antiseizure medications (valproate, levetiracetam, and clonazepam) administered for 9 days, gradually improved after PER was started. In addition, myoclonus recurred when the drug was withheld due to patient’s dry mouth or pickled extremities. By reintroducing PER, myoclonus improved without other side effects. For this reason, we believe that the early introduction of PER in Lance-Adams syndrome after cardiac arrest is worth considering.