A blackout means not being able to remember what happened when you were drinking or using drugs. Blackouts are not the same as passing out. Passing out occurs when you lose consciousness. You don't pass out when you have a drug or alcohol blackout. In a blackout, you lose short-term memories. A blackout is a type of amnesia.

During a blackout, you may function normally. People around you may not notice anything different about your behavior. You might do the things you normally do, such as eat dinner, wash dishes, or watch television, but later you have no memory of doing them.

Many people who have blackouts aren't worried about them. They might remember feeling good but be unable to remember what they did. This is called euphoric recall. Other people find blackouts very disturbing and seek treatment because of them.

You may pass out during a blackout. This can be caused by the effects of the alcohol or drugs, a head injury from a fall when you were drunk or high, or a seizure. You probably will not remember hurting yourself or having a seizure.

If you think you have blackouts, don't drive or operate any kind of machinery. Talk to your doctor about your blackouts. You might need to be tested for other problems that can cause loss of consciousness.