Pyridoxine-dependent epilepsy (PDE-ALDH7A1) is a metabolic encephalopathy characterized by an intractable epilepsy that is often unresponsive to antiseizure medications.1,2 Treatment with pharmacologic doses of pyridoxine (vitamin B6) results in clinical improvement and long-term seizure control, although intellectual and developmental disability (IDD) persist for the majority of patients.3 The degree of cognitive impairment does not correlate with time of seizure onset or severity suggesting a separate disease mechanism for the IDD.3,4. This evidence concerns the gene ALDH7A1 and pyridoxine-dependent epilepsy.