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What is Auto Brewery Syndrome and How Can it Lead to DWIs

As a seasoned DWI lawyer, I have encountered various cases that initially appear perplexing. One such case is that of Auto Brewery Syndrome (ABS), a rare medical condition that can lead to individuals becoming intoxicated without ever consuming alcohol. Also known as gut fermentation syndrome or endogenous ethanol fermentation, this intriguing condition has raised eyebrows in legal circles. In this blog post, we will delve into what ABS is, how it can affect individuals, and the legal challenges it presents.

What is Auto Brewery Syndrome?

Auto Brewery Syndrome is an unusual and poorly understood medical condition where the affected person's digestive system produces excessive amounts of alcohol after consuming carbohydrates. Typically, the gut contains yeast and bacteria that assist in breaking down carbohydrates during digestion. In ABS, certain strains of yeast present in the digestive tract can convert these carbohydrates into alcohol. The alcohol produced enters the bloodstream, leading to intoxication.

How Does ABS Lead to Intoxication?

Individuals with ABS may exhibit symptoms of intoxication, including slurred speech, impaired coordination, and altered mental states, even if they haven't consumed any alcoholic beverages. The condition can result in a person registering a high blood alcohol concentration (BAC) on a breathalyzer test, despite having no alcohol in their system.

It is crucial to distinguish between individuals genuinely affected by ABS and those attempting to use it as a defense for driving under the influence. ABS cases can be challenging to identify, as symptoms may mimic those associated with alcohol consumption, making it essential for experienced DWI lawyers to navigate the complexities of such cases.

Diagnosing Auto Brewery Syndrome

Diagnosing ABS can be difficult as it mimics the effects of alcohol intoxication. Medical professionals may need to rule out other possible causes, such as diabetes, liver diseases, or gastrointestinal disorders, before arriving at an ABS diagnosis.

Typically, the diagnostic process may involve the following steps:

1. Detailed Medical History: A comprehensive medical history is crucial to identify patterns of symptoms and potential triggers.

2. Blood Tests: Measuring the blood alcohol concentration during periods of apparent intoxication and sobriety can help establish the presence of alcohol production in the body.

3. Fecal Analysis: Analyzing stool samples to identify the presence of specific yeast strains responsible for alcohol fermentation.

4. Carbohydrate Challenge Test: Under controlled medical supervision, the patient may be given a carbohydrate-rich meal to observe if it leads to elevated BAC levels.

Legal Challenges of ABS Cases

Auto Brewery Syndrome poses unique legal challenges when it comes to DWI cases. Defending individuals accused of driving under the influence while suffering from ABS requires specialized expertise. Several factors complicate the defense:

1. Lack of Awareness: Law enforcement officials and legal professionals may not be familiar with ABS, leading to skepticism about the legitimacy of the condition.

2. Timing of Tests: To establish the ABS defense, accurate BAC tests need to be conducted during both periods of intoxication and sobriety, which can be challenging to coordinate.

3. Proof of Diagnosis: Courts may require concrete medical evidence to support the ABS defense, which can be difficult to obtain due to the rarity of the condition.


Auto Brewery Syndrome is a rare and medically intriguing condition that can lead to individuals experiencing alcohol intoxication without ever consuming alcoholic beverages. For those accused of DWI while suffering from ABS, seeking the expertise of an experienced DWI lawyer is crucial. Proving the existence of this condition and building a strong defense can be complex, requiring a comprehensive understanding of both medical and legal aspects.

As an advocate for justice, it is essential to raise awareness of this condition to ensure that individuals genuinely affected by ABS are treated fairly and lawfully. Legal professionals must stay updated with the latest research and medical advancements to navigate the complexities of DWI cases involving Auto Brewery Syndrome with competence and empathy.