RSA staff must understand that intoxication begins when the first drink of alcohol is consumed and commences its passage through the human body. When alcohol builds up in a person’s bloodstream, it can significantly affects the drinker’s understanding of events and their outward behaviour. The body quickly absorbs alcohol. However, the exact time that the body will take to absorb alcohol will vary from one person to another. There are many factors that affect BAC.
Gender – Females tend to have a slightly higher BAC than men after drinking the same amount because they have less body fluid to dilute the alcohol.
Size – Smaller people are affected more than larger people for the same reason.
Fitness level – It may take longer for a fit person with more muscle tissue and less fat to be affected by alcohol, as lean muscle tissue contains around 65% more water than body fat.
Health – Being tired, ill or stressed may affect a person’s reaction to alcohol. The central nervous system is under stress when a person is tired or ill. Alcohol is a depressant and places more stress on the body’s systems, which may result in the person being more quickly affected by alcohol.
Age – As a person ages their total body water tends to decrease, so that a given amount of alcohol will produce a higher BAC.
Psychological – An unhappy or depressed state of mind may be increased when a person drinks alcohol. Two drinks when a person is depressed or unhappy may have the same effect as four drinks would normally have.
Rate of drinking – If a person drinks alcohol quickly it will have a greater effect because they are drinking at a faster rate than their body can remove it.
Drinking on an empty stomach – If there is food in the stomach, alcohol will mix with the food before passing to the small intestine. This slows down the alcohol being absorbed into the blood. However, the process is only slowed down – not stopped. Eventually, all of the alcohol consumed will be absorbed into the blood and will travel around the body, but the BAC will not rise to the same levels as they would if the person hadn’t eaten.
Medication – Many medications will interact with alcohol. This increases the potential for loss of control of behaviour and can be dangerous. Therefore, people should avoid drinking alcohol when taking medication.
Illicit drugs – Mixing illicit drugs such as cannabis, heroin, cocaine, methamphetamine or ecstasy with alcohol can have dangerous or lethal consequences. People should avoid mixing alcohol and drugs.
RSA staff need an understanding of the external factors that affect intoxication in order to serve alcohol responsibly.