sir i have a sister aged 23 having a problem that without any sign of illness at a sudden she get faintaed.she is suffering from this for last 7 years.the frequency of her geting fainted vary,sometimes once in a week,or sometimes she remain quit well for 1 or even 2month and we think now she is ok but and again get fainted.she also suffer from sever headache.we visited many doctors many test done,but no any positive result?doctors and test say every thing is ok. sir,plz suggest something.cant she be treated and become well like before.she has been a very bright student but because of this she is not able to study. kindly suggest something. thanking you rahul kumar