I am on lamotrigine for another illness (bipolar disorder). My neurologist suggested it may help with VS and suggested I increase my dose from 200mg/day to 400mg/day. This appeared to significantly improve my positive afterimages. However I did not think it was worth pursuing, as: 1) It is an expensive drug, and 2) Side effects were a bit much, a bit spaced out all the time and also it multiplied the effects of alcohol by about 4. May be different for different people and I'd be interested to see if anyone gets any positive (or negative) effects.