Auto-Brewery Syndrome Very rare but There have been instances of people suffering from this syndrome being pulled over to take the breathalyzer test, to find out that the alcohol level in their bodies were several notches over the permissible limit, even though they hadn't touched a drink. A type of yeast present in the stomach and intestines ferments carbohydrates to produce ethanol which in turn intoxicates the person even without drinking. This is one of the examples of weird medical conditions.
I have actually read about a case like that! The person was not allowed to drive anymore π