One reason that alcohol-impaired drivers are likely to drive more poorly is

The answer is: They think there is nothing wrong with their driving

Alcohol would impair our ability to make a proper decisions, but in the perspective of the drunk people, they do not think that they are doing anything weird or stupid. Because of this, they would still maintain the full speed even when their response time is extremely impaired, causing large number of accidents.

answer; delirium is a common adverse reaction seen when elderly patients take diphenhydramine;