Auto-brewery syndrome causes people to become intoxicated without drinking alcohol as their bodies turn ordinary carbohydrates into ethanol, leading to bizarre cases of false DUI accusations and unexplained drunkenness.
At a Glance
- Auto-brewery syndrome (ABS) occurs when fungi or bacteria in the gut convert carbohydrates into alcohol, causing intoxication without drinking.
- Symptoms mimic alcohol intoxication including brain fog, dizziness, slurred speech, and high blood alcohol levels.
- Risk factors include recent antibiotic use, diabetes, high carbohydrate diets, and gastrointestinal disorders.
- Treatment involves low-carbohydrate diets, antifungal medications, and probiotics to restore gut balance.
What Causes the Body to Become Its Own Brewery?
Auto-brewery syndrome (ABS) develops when certain microorganisms colonize the gastrointestinal tract in excessive numbers, particularly yeast species like Saccharomyces cerevisiae and Candida, or bacteria such as Klebsiella pneumoniae. These organisms ferment carbohydrates and produce ethanol as a byproduct, just like the brewing process used to make beer or wine. The condition most commonly affects the gut, but cases have been documented in the bladder (urinary auto-brewery syndrome) and oral cavity as well.
Several factors can trigger ABS development. Recent antibiotic use disrupts the natural balance of gut flora, allowing opportunistic yeasts to flourish. People with diabetes experience higher glucose levels that feed fermenting organisms. Inflammatory bowel conditions like Crohn’s disease and dietary patterns high in simple carbohydrates and sugars create environments where fermenting organisms thrive. Immunocompromised individuals also face higher risks as their bodies struggle to regulate microbial populations.
Recognizing the Symptoms of Internal Fermentation
What makes ABS particularly challenging is that its symptoms directly mimic alcohol intoxication. Affected individuals experience brain fog, confusion, dizziness, coordination problems, fatigue, and mood changes without consuming alcoholic beverages. Blood tests reveal elevated alcohol levels despite abstinence from drinking. Many patients report feeling worse after consuming carbohydrate-rich meals, as these provide more “fuel” for the fermenting organisms to produce alcohol.
The social and legal implications can be devastating. People with undiagnosed ABS have faced DUI charges, employment problems, and strained relationships when accused of secret drinking. One notable case involved a woman who was cleared of DUI charges after providing evidence she suffered from the syndrome. The unpredictable nature of the condition means someone might appear perfectly normal in the morning but become visibly “intoxicated” after lunch, creating significant challenges in daily functioning.
Diagnosing This Rare Condition
Diagnosing ABS requires ruling out actual alcohol consumption and other conditions with similar symptoms. Healthcare providers typically begin with a comprehensive medical history and physical examination. Blood and breath tests that show elevated ethanol levels without alcohol consumption provide important clues. Some physicians employ a carbohydrate challenge test, monitoring blood alcohol concentrations after consuming carbohydrates under controlled conditions to observe if fermentation occurs.
Stool samples may be analyzed to identify the specific microorganisms causing fermentation. Comprehensive testing for underlying conditions that might contribute to gut dysbiosis is also important. Because ABS remains underdiagnosed, patients often endure years of symptoms and misdiagnoses before receiving proper identification. Healthcare providers should consider ABS when evaluating unexplained intoxication, especially in patients with risk factors like recent antibiotic use or gastrointestinal disorders.
Treatment Approaches and Management
Effective treatment for ABS begins with dietary modifications. Patients are typically advised to follow a low-carbohydrate, high-protein diet that limits the “fuel” available for fermenting organisms. Simple sugars and refined carbohydrates are particularly problematic and should be strictly limited. Antifungal medications like fluconazole or nystatin are prescribed to reduce the population of fermenting yeasts. In cases where bacteria are the primary fermenters, targeted antibiotics may be used cautiously.
Probiotics help restore healthy gut flora, while treating underlying conditions like diabetes or Crohn’s disease is essential for comprehensive management. Some severe cases have responded to fecal microbiota transplants, which introduce healthy gut bacteria to reestablish microbial balance. Relapse prevention focuses on maintaining dietary restrictions, avoiding unnecessary antibiotics, and regular monitoring. Most patients can achieve significant improvement with proper treatment, though some may require ongoing management.
