Case series of HaNDL syndrome responding to valproic acid

Objective: We report a case series of patients diagnosed with the syndrome of transient headache and neurological deficits with cerebrospinal fluid lymphocytosis (HaNDL) responding to high dose Valproic acid. Background: HaNDL syndrome is an infrequent entity, presenting with neurological impairment episodes and severe headache. A treatment to prevent the attacks has not been proposed yet. Results: We describe 6 patients with a definite diagnosis of HaNDL, responding to Valproic acid 1000–1500 mg/day. Conclusion: Although HaNDL’s self-limiting nature, episodes may cause important disability and can last up to 3 months. Valproic acid may be a good choice to prevent attacks due to its effect on cortical depression and fast titration.