###Human: Fever with low WBC count. Could Eptoin be the cause? ###Assistant: Hello. I understand your concern and would explain that Eptoin (Phenytoin) is a drug used to treat or prevent seizures. It does not usually affect WBC, but very rarely (like all the drugs) it can cause suppression of the blood cell formation in the bone marrow. The low WBC count can be related to different possible causes like viral disease, an autoimmune disorder, drug adverse effects, etc. A myelogram may be needed to exclude a possible hematological disorder. In the meantime, I recommend taking Eptoin, as it is well known that high fever can lead to seizures. I would also recommend taking steroids, because they can increase WBC and also help fight the fever.