Electronegative electroretinogram associated with topiramate toxicity and vitelliform maculopathy

Topiramate is known to cause ocular side effects such as refractive changes and angle closure. We describe a patient with an electronegative electroretinogram (ERG) which may have been related to topiramate use. Electronegative ERG’s have been associated with other drugs in humans as well as topiramate use in rabbits. However, this would be the first suggestion of causality in humans.