Hal has been diagnosed with Auto-Brewery Syndrome (ABS), a little-known medical condition that causes his body to make ethanol without drinking – leaving him dangerously intoxicated. His son, Tristan, who recently quit his job and moved home to help care for Hal, says he’s noticed a dramatic change in his father’s personality and day-to-day communication skills. He says that when Hal is having an ABS flare-up, he is often paranoid and sometimes hallucinates.

“He could be in the walls, thinking people in the walls are talking to him,” says Tristan. “I don’t think he understands how bad it can truly be and the effect that it has on others.”

Tristan and Hal’s girlfriend of 15 years, Stephanie, both say that when Hal is in the midst of an ABS episode, he becomes verbally abusive, belligerent, and sometimes physically aggressive. They say he is also prone to falling, and once - severely injured himself during a tumble.

Hal says that generally, he only remembers “bits and pieces” of his ABS episodes, and then, usually only after the fact. How does he describe his experience living with the disorder? Watch Friday’s Dr. Phil, “Belligerent and Blacked Out But Not a Drop to Drink,” to find out.

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WATCH: ‘You Wake Up And You’re Out Of Your Mind,’ Says Man Living With Auto-Brewery Syndrome

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