Drinking a lot of alcohol quickly can cause a blackout

There are a lot of misconceptions about blackout drinking, according to an alcohol abuse researcher and addiction medicine specialist recently interviewed by NPR. It’s important to understand the reality of blackouts so you can avoid the trouble they cause.

When people hear of a drinking-related blackout, they often picture someone who has passed out and cannot be roused. In reality, passing out is a separate phenomenon, according to Dr. Richard Saitz, chair of Boston University School of Public Health’s Department of Community Health Sciences. A blackout is a loss of memory for a period of time — and it can occur without the drinker passing out at all.

It might be clearer to use the term “alcohol-induced amnesia.” According to Dr. Saitz, this amnesia commonly occurs when people drink a significant amount of alcohol in a short period of time, such as in a drinking game. The amnesia can be total, or memories may be spotty.

The person can seem fully awake and even active during a period that is later forgotten. What is happening, essentially, is that the drinker’s brain isn’t recording the memories into long-term storage. They might have short-term memories allowing them to seem coherent, but hours or days later the events have simply disappeared from the person’s memory. According to Dr. Saitz, this probably has to do with how the frontal lobes and hippocampus of the brain are affected by high alcohol concentrations.

There is not much data on how common alcohol-induced amnesia may be, but perhaps 10 to 50 percent of young people have experienced it. In any case, the phenomenon isn’t rare.

Another misconception, according to Dr. Saitz, is that alcohol-induced amnesia is a symptom of alcoholism, or that only alcoholics experience it. That simply isn’t the case. Not all binge drinkers suffer from alcohol use disorder, yet anyone who drinks a sufficient amount of alcohol quickly enough could experience alcohol-induced amnesia.

It may not take that many drinks to suffer amnesia

According to the Centers for Disease Control and Prevention, on average it takes about five drinks for men or four drinks for women within about two hours to reach a blood-alcohol concentration of 0.08%. However, blood alcohol concentration depends on numerous factors including gender, weight, when and what you have eaten, what you are drinking, tolerance, fatigue, medications, etc. Depending on the individual, it might not take many more drinks than that to induce amnesia.

Acute alcohol intoxication causes changes to the brain that lead to poor judgment, impaired balance and motor skills, reduced reaction time and other effects even if alcohol-induced amnesia does not occur. It is never safe to drive when intoxicated.

If you have been arrested for drunk driving, contact an experienced criminal defense attorney.

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