I read your question carefully and I understand your concern. From that description it seems that that is the case of an epileptic seizure. Having a single epileptic seizure doesn t necessarily mean to have epilepsy though, many people can have isolated seizures, especially when exposed to factors lowering seizure threshold like alcohol consumption or other substances, lack of sleep etc. So having just the one epileptic seizure doesn t mean one is doomed to develop epilepsy. She should undergo some examinations for possible causes of seizures, like routine blood tests (blood count, blood sugar, liver and kidney function tests, electrolytes), an EEG to look for abnormal epileptiform electric activity in the brain and brain imaging preferably with MRI to exclude possible brain lesions like tumor, stroke etc. A cardiac evaluation might be considered at times when in doubt as to the nature of the episode to check for arrhythmias or other heart conditions causing a transitory lack of blood flow to the brain. The results of those tests will give some indication on how likely she is to have more seizures (although their coming back normal doesn t exclude that possibility). I hope things work out for the best.