These medicines may be used for a short time, and then tapered off. Sometimes, the improvement in seizures lasts for a long time after the medicines are stopped. Its mechanism of action is not clear, but it is effective for partial and for generalized epilepsies. Aplastic anemia and liver damage are rare, but may be fatal. Currently felbamate is available for those cases where the severity of the epilepsy warrants its use.
Drowsiness is the most common side effect.
Behavior disorders occur rarely. This drug is safe in humans in extensive studies, but has caused some brain changes in some animals. Vigabatrin is currently not available in the United States, except on experimental protocols. This diet requires that about 90 percent of the total calories must come from fats. This causes a shift in the body's metabolism so that fat is burned for energy rather than stored as body fat, or as cholesterol deposits.