A 100 pound person is usually twice as impaired as a 200 pound person by the same amount of alcohol. Safety experts say that before driving you should wait one hour for each drink consumed. It takes the body that long to turn up one beer or other drink. Black coffee and fresh air won't help. A person does not have to be really drunk to be a dangerous.
Alcohol works in much the same way.
Someone who drinks too much can actually stop breathing and die. Persons who have consumbed a large amount of pass out after drinking may be in danger. Rush them to the emergency room of a hospital. There life-saving actions can be taken. Central nervous system depressants and alcohol together are more dangerous than either by itself.