Anti-seizure medication to take DURING seizure?

I know that if you have epilepsy or are otherwise prone to seizures, that you can be prescribed an anti-seizure medication like Dilantin or Keppra to take regularly.

But are there any medications you can take at the onset of a seizure to stop it before it really gets going?

P.S. This is specifically for seizures occurring months after a hematoma - the hematoma is healed but it's not unusual to get seizures for months/years after.