In another befuddling medical case, a 46-year-old man who has been a teetotaler all his life got a shock when he discovered his own stomach was brewing beer.

The unidentified man who didn't consume a drop of alcohol would always fail the breathalyzer test while driving and the cops would think he's just lying to get away.

Frustrated with what he was going through, the man decided to get things sorted at a doctors. That's when he got the shock of his life.

Doctors revealed that he had a certain kind of bacteria in his stomach lining that was turning carbs into beer. According to reports, the doctors found high levels of a specific fungus called Saccharomyces cerevisiae was found in his stool.

The same fungus is used by beer makers to convert carbohydrates into alcohol. It is also known as brewer's yeast.

The tests proved that the fungus was present in his stomach. That meant every time he consumed carbohydrates, they got converted into beer in his belly. "The hospital personnel and police refused to believe him when he repeatedly denied alcohol ingestion," researchers from Richmond University Medical Centre said.

"For years, no one believed him," one of the medical team, Fahad Malik, now a chief medical resident at University of Alabama at Birmingham, told New Scientist.

Reports state that his condition started after consuming some antibiotics that he was prescribed for his thumb injury in 2011.

He said that because of it he had been experiencing memory loss, mental fogginess and dizziness.

He was treated at Richmond University. Specialists there managed to use probiotics to reduce the fungus and help regulate the man's gut.