The use in epilepsy is among its historically oldest indications of cannabis. Animal experiments provide evidence of the antiepileptic effects of some cannabinoids. The anticonvulsant activity of phenytoin and diazepam have been potentiated by THC. According to a few case reports from the 20th century, some epileptic patients continue to utililize cannabis to control an otherwise unmanageable seizure disorder. Cannabis use may occasionally precipitate convulsions.