Epilepsy is caused by excessive and synchronous discharge of cerebral neurons resulting in seizures. Seizures can be detected by EEG and categorized by origin, etiology, clinical presentation, and electrophysiology. They are broadly classified as partial or generalized. Anti-epileptic drugs work by enhancing GABA, inhibiting sodium channels, inhibiting calcium channels, or blocking glutamate receptors. Phenytoin is a first-line treatment for tonic-clonic, simple partial, and complex partial seizures as well as status epilepticus. It has many potential adverse effects and drug interactions that require monitoring.