Dilantin; Dilantin Kapseals; Phenytek 

Phenytoin sodium (marketed as Dilantin® in the USA and as Epanutin® in the UK, by Parke-Davis, now part of Pfizer) is a commonly used antiepileptic. It was approved by the Food and Drug Administration in 1953 for use in seizures.

Ectopic heartbeat as related to Phenytoin