Mark Mongiardo's life unraveled after unexplained intoxication episodes. In 2019, despite consuming only a soda and fries, a breathalyzer showed his blood alcohol level at .18 percent, leading to a second DUI charge. His career as a gym teacher ended after repeated warnings colleagues smelled alcohol on him.

Similarly, Joe Bartnik, a nurse, suffered inexplicable drunkenness at church and in public, registering a .37 percent BAC after a 2009 ambulance call. Doctors repeatedly dismissed them as closet alcoholics. The condition, Auto-brewery syndrome, involves gut microbes fermenting carbohydrates into ethanol, causing intoxication without drinking.

Diagnosis is rare and difficult, often requiring specialized testing after multiple misdiagnoses. Doctors like Dr. Prasanna Wickremesinghe and Dr. Fahad Malik are now documenting cases, finding it may be more common than thought.