Loss of consciousness (unconsciousness)

When a person experiences a loss of consciousness, he or she is neither awake nor aware of the external environment. Loss of consciousness often is described as being "knocked out."

Attempts to arouse an unconscious person to an alert state may not be successful. The person may not respond at all or may respond with moans or nonpurposeful movements.

A loss of consciousness for longer than 60 seconds needs to be evaluated by a health professional.

Any loss of consciousness after a head injury, even if only for a short time, requires immediate evaluation by a health professional.

Last Updated: July 9, 2008

Author: Jan Nissl, RN, BS

Medical Review: Michael J. Sexton, MD - Pediatrics & H. Michael O'Connor, MD - Emergency Medicine

related physicians

related services

Bon Secours International| Sisters of Bon Secours USA| Bon Secours Health System

This information does not replace the advice of a doctor. Healthwise disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Privacy Policy. How this information was developed to help you make better health decisions.

© 1995-2010 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.