Amphetamine-associated seizures: clinical features and prognosis.

Forty-four patients presenting with first-ever seizure within 24 h of illicit use of amphetamine or related analogs (amphetamine-associated seizures, AAS) were identified over 8 years. Patients with AAS were compared to control groups of other first-ever seizure patients (provoked n = 126 and unprovoked n = 401). Cumulative probability of recurrence was calculated using Kaplan-Meier analysis. Seizure recurrence and development of epilepsy were less likely in patients with AAS compared to provoked or unprovoked controls. Forty percent of patients with AAS had clinical risk factors for epilepsy, epileptiform abnormalities on electroencephalography (EEG), or an epileptogenic lesion on neuroimaging. Sleep deprivation was more frequently present in those with AAS. AAS likely relate to an intrinsic proconvulsant effect of these drugs combined with patient susceptibility and environmental factors.