Serotonin reuptake inhibiting antidepressants: A trigger for visual snow syndrome?

BackgroundVisual snow is an abnormal visual perception, frequently occurring in the context of visual snow syndrome. Recent literature has suggested a link with serotonin reuptake inhibiting antidepressants, but there is little research on this topic.ObjectiveWe aimed to identify cases of visual snow and visual snow syndrome linked to serotonin reuptake inhibiting antidepressants to evaluate the possibility of an association.MethodsRetrospective analysis of patient adverse event reports linking serotonin reuptake inhibiting antidepressants with visual snow or visual snow syndrome using data from RxISK.org, a global database of spontaneous reports of drug-linked adverse events. Each case was subject to a causality assessment: a RxISK score of 0-4 indicates more information is required, 5-8 a likely link and ≥9 a strong possibility of a link between the medication and the symptoms.Results24 cases were identified; 16 male and 8 female patients, with a mean age of 30 years. All had visual snow, and 10 patients (42%) had visual snow syndrome. Reports originated from 8 countries and involved 10 different drugs. Symptoms began on the drug in 14 cases (58%), after reducing the dose in 6 cases (25%), and after discontinuation in 4 cases (17%). At the time of reporting, 22 patients (92%) had stopped the suspect drug but without resolution of symptoms. The mean RxISK score was 9.5 (range 2-17).ConclusionSerotonin reuptake inhibiting antidepressants may trigger visual snow and visual snow syndrome that fails to resolve or can even worsen or emerge after stopping the drug. With usage of these medications rising worldwide, cases are likely to increase. Further research is vital to understand potential mechanisms and risk factors.