Black out

Hi I am a 21 year old male and the other night I was at a concert and I was standing up for about 3-4 hours.  My friend next to me started feeling sick so I bent down to help her, and when I stood back up and started walking towards the exit, my legs collapsed and my vision went black. I couldnt see anything. I fell to the ground and I think my legs were shaking.  A couple seconds later, I got back up and made it to the exit where I sat down and people gave me water.  I was sweating real bad.  I vomitted the water a little and about 10 min later, I was fine and I went back into the concert.  Also, I really didnt eat anything all day except a frozen dinner for lunch at about 11:30a.m.  and the blackout occured at about 10:30 p.m.  This has never happened before, and I am wondering if this is something I should be concerned about.  Thank you very much

Justin

[CCF-M.D.-CRC]

Dear Justin,

Fainting, or syncope, is a common occurance and is usually benign.  The most common form is called vasovagal syncope or 'the common faint'.  This may be brought about by standing in one place for prolonged periods, standing up suddenly, or strong emotions such as the sight of blood.  A cold sweat will often accompany this and usually the individual does not sustain any injuries.  There is usually a clear factor that brings about the faint.

Other more malignant forms of fainting would include those due to seizures or heart arrhythmias.  These may occur standing or sitting.  They occur suddenly without warning.  The person may injure themselves during the 'faint'.  Usually the history will help to lead the doctor in making the diagnosis for more serious types.