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Harvard Reviews of Health News

Americans with diabetes are much less likely to develop further health problems than they were 20 years ago, a new study finds. But the actual number of people with diabetes has more than tripled. The study used data from several national surveys and database...

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Senior's Health


Blacking Out, Fainting, or Loss of Consciousness

Welcome.

The two main reasons for blacking out are insufficient blood flow to the brain and abnormal electrical activity within the brain (a seizure).

While both of these sound scary, in reality most episodes of blacking out are not related to life threatening health problems.

This guide is designed to provide insight into why you passed out. It is not a diagnostic tool or a substitute for evaluation by a health professional.

The questions are ones your doctor is likely to ask you. Your answers provide a path to better understanding of the common reasons for losing consciousness.

Let's begin.

Date Last Reviewed: 7/31/2009
Date Last Modified: 7/31/2009