The man, who dabbles in home-brewing, went to a Texas emergency room complaining of dizziness. Nurses ran a breathalyzer test, and his blood alcohol concentration was at 0.37 percent: nearly five times the legal limit for driving in Texas.
But the man said he had not had even a sip of alcohol that day.
"He would get drunk out of the blue -- on a Sunday morning after being at church, or really, just anytime," says Barbara Cordell, the dean of nursing at Panola College in Carthage, Texas. "His wife was so dismayed about it that she even bought a Breathalyzer."
Some of the doctors thought the man was a "closet drinker" and shrugged it off. Cordell and Dr. Justin McCarthy, a gastroenterologist in Lubbock, were not convinced.
Once he and his belongings were searched for alcohol, they kept him isolated in a hospital room for 24 hours. There, they fed him carbohydrate-heavy foods and monitored his blood alcohol level. At one point, it rose 0.12 percent.
McCarthy and Cordell found out where he was getting his buzz: His intestinal tract was acting as his own internal brewery.
He had an infection with Saccharomyces cerevisiae -- related to too much brewer's yeast in the gut. When he ate or drank starchy foods, the yeast fermented the sugars into ethanol and caused him to get drunk.
The case is very uncommon, as brewer's yeast is found in a myriad of ordinary food and is usually digested. But sometimes, as in the patient's case, it can take hold in the gut and cause long-term problems.
The patient is now on a low-carb diet and an antifungal medication to keep his alcohol levels down, but because the syndrome is relatively unknown, few known medical treatments are available. So far, the man has been able to keep his alcohol levels low enough to return to normal.