KCNQ2 and Encephalopathy: Among the 20 patients that did not respond, 15 were affected by KCNQ2 epileptic encephalopathy and responded to a combination of several drugs, including sodium channel blockers, topiramate, and levetiracetam [43, 60]; Of the remaining patients, 3 were affected by KCNQ3 encephalopathy, and 2 of these patients dramatically responded to intravenous levetiracetam [43].