Seizures, including subclinical seizure activity, can complicate clinical courses and increase progression of brain herniation in persons with cerebral edema and increased intracranial pressure. Anticonvulsants can be used to treat seizures caused by acute brain injuries from a variety of origins. However, there are no clear guidelines on the use of anticonvulsants for prophylactic use. Their use may be warranted on depending on the clinical scenario and studies have shown that anticonvulsants such as phenytoin can be given prophylactically without a significant increase in drug-related side effects.