Which medication is typically administered to a patient who has experienced a generalized tonic-clonic seizure?

Phenytoin is commonly administered as a first-line treatment for generalized tonic-clonic seizures, particularly in emergency situations. It works by stabilizing neuronal membranes and reducing the excitability of neurons, which is crucial during or following a seizure episode. This medication is often preferred because it can be given intravenously for rapid control of seizures in acute settings, making it particularly effective for patients who require immediate intervention.

Other medications listed, such as valproic acid, carbamazepine, and lamotrigine, are also used to manage epilepsy and can be valuable in treating various seizure types or for long-term management. However, phenytoin's rapid onset of action and established use in emergency scenarios make it a top choice specifically for calming generalized tonic-clonic seizures right after they occur.