seizures
"This has helped control my complex partial seizures in combination with Neurontin, which I have been on since 1994.  I have been on Vimpat for about 17 months now and it causes short/long term memory problems.  I can't be on high doses of this.  Sometimes I will be in mid-sentence and have to stop talking just trying to get the word(s) off the tip of my tongue.  It also causes sleep problems and decreased appetite as well."