Q:

Does blacking out from drinking cause brain damage?

A:

"Black out", for purposes of this discussion in the context of drinking alcohol, means not remembering what transpired during the time of intoxication, so that there is a period of amnesia and that, by definition, implies brain dysfunction and sometimes "delirium". The brain is drug affected, unable to perceive reality in a normal way and unable to process or recall information during that time. Obviously there is significant risk of an intoxicated person in "black out" having poor judgment, making decisions that put their well being at risk because of their situation (i.e. driving, sexual, or other) that can result in acute injury or death, a much bigger deal than the long term risk of brain damage.

Blacking out is different from "passing out" which is drug induced unconsciousness, with risk of sedation that interferes with normal airway management and self protective reflexes, and high risk of death as a result.

Any drug induced state of altered mental status is causing brain cell injury, and with enough repeated exposures/incidents, chronic damage happens from that injury or brain cell death resulting in impaired cognition (thinking/remembering) and neurologic functioning (weakness, numbness, reflexes) on a permanent basis.