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What’s the difference between blacking out and passing out when you drink?

Lonely Mand with Vivid MemoriesWhat does it mean to have a blackout when you’re drinking? How is it different from passing out? And do people really forget what they did or said, or what happened to them, when they experience a blackout after drinking?

If you drink too much, too fast, you may experience a blackout. They occur when large amounts of alcohol are consumed quickly, creating a rapid rise in blood alcohol content (BAC).

When you have an alcohol-induced blackout, the functioning of your hippocampus is affected; the hippocampus is the part of your brain that assists in the formation, storage, and creation of memories. Basically, alcohol impedes the ability for information to transfer from short-term memory to long-term storage, so memories are not created, or aren’t created properly. So yes, it’s common to have trouble remembering things after a blackout.

There are two types of alcohol-induced memory problems caused by blackouts:

  1. en bloc (total): the person is unable to recall any information from a specific period of time; they usually occur when the person who blacks out has a higher BAC.
  2. fragmented (partial): these are more common, occur at lower BACs, and may allow for some amount of memory recall.

Blackouts are different from passing out, which involves a visible change in consciousness—in other words, the person stops functioning and may appear to be asleep. People who blackout, though, may appear to be functioning normally, carrying on conversations and being able to behave as if they’re not affected. But because the information gathered during blackouts isn’t stored in long-term memory, you may not remember much or anything that happened that night, the next day.

The risk of blacking out due to alcohol use varies from person to person. Unfortunately, those who are at highest risk of blacking out are teenagers between the ages of 15 and 19. In a recent study of teenage alcohol users, 30 percent of 15-year-olds had experienced a blackout, while 74 percent of 19-year-olds had. Only 5 percent of the participants never experienced a blackout at any point between the ages of 15 and 19, and almost a third of the participants experienced more blackouts as they grew older.

Some factors that increase the risks for blackouts among teenage drinkers:

  • having a generally high level of alcohol intake
  • being female
  • smoking cigarettes
  • hanging out with people who regularly engage in drinking and doing drugs
  • being a rule-breaker or someone who often acts impulsively

If you have any questions about drinking and blacking out or passing out, it can be the one of the warning signs of alcoholism, please call or contact Horizon Health Services at (716) 831-1800. We’d be happy to help.