We encountered a female patient with late-onset temporal lobe epilepsy who presented with transient amnesia as the sole ictal manifestation, an accelerated rate of forgetting daily life events, and a retrograde memory deficit. We describe the memory function of the patient both before and after the administration of antiseizure medication. After the patient's seizures were controlled with antiseizure drugs, her neuropsychological memory performance scores showed improvement. We presumed that the disappearance of seizures was associated with a decrease in the accelerated rate of forgetting medication. However, her lost memories were not recovered after the seizures were controlled by antiseizure medication.