Treatment effects and comorbid diseases in 58 patients with visual snow

OBJECTIVE: To evaluate pharmacologic treatment options for visual snow and to report prevalence of comorbid diseases. METHODS: Medical charts of patients with a diagnosis of visual snow at the neurology outpatient clinic were reviewed on prescribed medication, and comorbid migraine, tinnitus, and psychiatric conditions including depression and anxiety. RESULTS: From 2007 to 2018, 58 patients were diagnosed with visual snow. Comorbid migraine was present in 51.7% of patients, lifetime depression in 41.4%, and lifetime anxiety in 44.8%. Lamotrigine was prescribed most frequently (26/58) and resulted in partial remission of symptoms in 5/26 (19.2%). No patients reported complete remission. Adverse events occurred in 13/26 (50.0%) patients. None of the other prescribed drugs (valproate [n = 7], topiramate [n = 4], acetazolamide [n = 2], flunarizine [n = 1]) led to improvement except for topiramate in one patient, who discontinued, however, because of adverse events. CONCLUSIONS: Of medication prescribed (lamotrigine, valproate, acetazolamide, flunarizine), only lamotrigine afforded some improvement in a small minority of patients. Migraine, depression, anxiety, and tinnitus were common comorbid diseases. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that for some patients with visual snow, lamotrigine resulted in partial remission of symptoms.