Seizure Medication

I have a friend who had a random seizure one morning after she had been vomiting and had diarrhea all night before.  She also had not been sleeping well or at all some nights the whole month before.  I took her to the emergency room and she had blood work done and a CT scan done both came back just fine.  The doctor told her it was probably that she was dehydrated, and had lack of sleep that put too much stress on her brain.  He also told her to consult a family doctor.  She doesn’t have insurance so she went to an appointment at the Peoples Clinic, a free clinic.  The doctor there gave her a physical and did blood work also (results not back yet) but prescribed Dilanten for her.  I looked up the drug and found it was an anti epileptic drug.
This was the first seizure she’s ever had with no family history either and she hasn’t had one since (it’s been about a week.)  My concern is that this is a highly toxic drug and I wonder if after just one seizure she should be taking it.  I told her to get a second opinion. What do you recommend?

[cell88]

im not a dr. but not after just one