A customer at 0.10% BAC drinks two large cups of black coffee. What is the effect on their BAC?
Explanation
Caffeine is a stimulant that may briefly mask drowsiness, but it does not increase the liver's rate of alcohol metabolism. The patron remains as impaired as before, only now more alert — sometimes called a 'wide-awake drunk' — which can actually increase risk-taking. Only time eliminates alcohol. The same myth-busting applies to cold showers, exercise, vomiting, and 'sleeping it off' for a short period. Servers must never tell a customer coffee will 'sober them up' enough to drive.
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