What is the cause for recurrent black outs?

Q: I am a 21 years old female. Over the last 4 years I have had 3 black outs, where I felt sick, dizzy and developed eye and hearing problems and would then black out. This last time I was out for about 2 minutes. I have told my doctor about this and he seems to think it is nothing to worry about. I have had other 3-4 episodes wherein I turned white like a ghost, had hearing loss but did not black out. Should I be concerned? What could this be?

A:Consider vasovagal attack or functional hypoglycaemia as the most likely causes of occasional fainting. Epilepsy is another concern, but no other serious diagnosis is likely if the condition is only occasional over the time span of a few years.