Can Kombucha Show Up as Alcohol on a Drug Test?

January 7, 2026 •

4 min read

Did you know that all fermented foods contain some level of alcohol, including kombucha? The trace alcohol content in kombucha raises a critical question for many: can kombucha show up as alcohol on a drug test?

Quick Summary

Kombucha contains trace alcohol from fermentation, which can cause false positives on breathalyzers or be detected by sensitive EtG urine tests, especially with homemade or improperly stored batches.

Key Points

Trace Alcohol is Inherent: Kombucha is a fermented drink, meaning it naturally contains trace amounts of alcohol, even in commercially sold, 'non-alcoholic' varieties.
Breathalyzers Can Be Tricked: Kombucha consumption can lead to a false positive on a breathalyzer test due to residual 'mouth alcohol,' especially if tested immediately after drinking.
EtG Urine Tests Are Highly Sensitive: Sensitive urine tests, such as EtG panels, can detect the metabolized alcohol from kombucha for several days after consumption.
Homemade Kombucha Poses Higher Risk: Home-brewed kombucha typically has a higher and more unpredictable alcohol content than commercial versions, increasing the risk of a positive test.
Avoid Kombucha When Abstaining: For individuals required to abstain completely from alcohol, kombucha should be avoided entirely to eliminate any risk of failing a drug or alcohol test.

The Science of Kombucha Fermentation

Kombucha is a fermented beverage made from sweetened tea and a symbiotic culture of bacteria and yeast (SCOBY). During the fermentation process, the yeast in the SCOBY consumes the sugar and converts it into ethanol (alcohol) and carbon dioxide. Later, the bacteria feed on this ethanol, converting it into various organic acids, including acetic acid. This dual-action fermentation process gives kombucha its signature tangy flavor and light carbonation.

Because alcohol is an inherent byproduct, all kombucha contains at least trace amounts of it. Commercial brands are legally required to keep their alcohol content below 0.5% alcohol by volume (ABV) to be sold as non-alcoholic in the U.S.. To achieve this, commercial brewers use controlled processes or post-fermentation methods to reduce the alcohol level. However, homebrewed kombucha can have higher and more unpredictable alcohol levels, sometimes reaching 1-3% ABV, depending on factors like fermentation time, temperature, and ingredients.

Factors Affecting Kombucha's Alcohol Content

Fermentation Time: A shorter fermentation favors yeast activity, resulting in higher alcohol content. Longer fermentation allows bacteria more time to convert the alcohol into acids, lowering the ABV.
Temperature: Warmer fermentation temperatures increase yeast activity and accelerate alcohol production.
Sugar Content: More sugar provides more fuel for the yeast to create alcohol.
Oxygen Exposure: More oxygen exposure favors the acetic acid bacteria, which reduces the alcohol content by converting it to acid.
Storage: Unrefrigerated kombucha can continue to ferment, increasing its ABV over time.

Kombucha and Breathalyzer Tests

A breathalyzer test is designed to measure the alcohol concentration in your breath, which correlates to your blood alcohol content (BAC). The risk of kombucha causing a false positive on a breathalyzer is real but primarily relates to 'mouth alcohol'.

When you drink or consume anything with alcohol, including mouthwash, certain medicines, or fermented foods, a small amount of residual alcohol vapor can linger in your mouth and oral cavity. If you take a breathalyzer test immediately or shortly after drinking kombucha, the device may pick up this temporary 'mouth alcohol' and produce a falsely elevated reading. This happened to a Minnesota Vikings player on probation who failed several tests after drinking kombucha.

The solution is simple: wait 15-20 minutes and rinse your mouth with water before taking the test. This allows any mouth alcohol to dissipate naturally. A subsequent, more accurate test (like a blood test) would show no significant alcohol in your system. However, for individuals with ignition interlock devices (IIDs) or those facing frequent testing, this can still be a significant concern.

Kombucha and Urine Alcohol Tests

For more advanced and sensitive testing, such as court-mandated probation, a urine test for alcohol metabolites like ethyl glucuronide (EtG) is often used. Unlike a breathalyzer, an EtG test does not measure current impairment but detects the presence of alcohol in the body for a much longer period, typically up to 80 hours after consumption.

A study published in ResearchGate examined alcohol markers in urine after consuming regular kombucha. The results showed that alcohol markers (EtG and EtS) were indeed detected in the urine of participants after drinking kombucha, though levels were below the cutoff for most standard immunoassay (IA) tests. This confirms that the body metabolizes kombucha's trace alcohol in the same way as alcohol from traditional beverages, producing detectable biomarkers. For individuals required to abstain from alcohol entirely, like those on probation, the trace alcohol in kombucha, even commercial varieties, is enough to cause a positive EtG test. Homemade kombucha, with its potentially higher alcohol content, poses an even greater risk.

Comparison of Testing Risks


Feature	Breathalyzer Test	Urine (EtG/EtS) Test
Detects	Current breath alcohol concentration (BAC)	Alcohol metabolites (evidence of recent consumption)
Primary Risk	False positive due to 'mouth alcohol' if tested immediately after consumption	Positive result from trace alcohol absorbed into the bloodstream
Risk Factor	Residual alcohol vapor in the mouth	Alcohol metabolized by the body
Timeframe	Immediate, temporary elevation	Up to 80 hours after consumption
Risk for Commercial Kombucha	Low, if waiting period is observed	Present, especially for sensitive tests
Risk for Homemade Kombucha	Higher potential for elevated readings	Significant risk due to higher, inconsistent ABV

Conclusion

While kombucha is widely considered a non-alcoholic beverage for casual consumption, its inherent alcohol content means it can cause a positive result on a drug test. The specific risk depends heavily on the type of test being administered. For breathalyzers, the risk is typically a temporary false positive caused by mouth alcohol, which can be mitigated by waiting and rinsing your mouth. For highly sensitive urine tests, particularly EtG tests used for probation and court orders, even the low levels of alcohol in commercial kombucha are enough to potentially trigger a positive result. The risk is significantly higher with home-brewed kombucha due to its less-controlled fermentation and potentially elevated alcohol content. Anyone subject to drug or alcohol testing should carefully consider these risks and discuss their consumption with their probation officer or medical professional. For more details on the regulations governing beverages like kombucha, consult the resources provided by the Alcohol and Tobacco Tax and Trade Bureau (TTB).

Frequently Asked Questions

Yes, kombucha can potentially trigger an ignition interlock device, especially if consumed shortly before testing. The device may detect 'mouth alcohol,' causing it to lock you out. Rinsing your mouth with water and waiting 15-20 minutes before testing can help mitigate this risk.

For most commercial kombucha with an ABV under 0.5%, it is unlikely to cause a standard blood alcohol test failure. However, a single bottle could cause a false breathalyzer reading and has the potential to trigger a highly sensitive EtG urine test.

Commercial kombucha is regulated to contain less than 0.5% ABV, making it a low but potential risk for sensitive tests. Homemade kombucha has a less-controlled fermentation process, often leading to a higher and more variable ABV (sometimes 1-3%), posing a much greater risk of a positive test.

To avoid a false positive from kombucha, rinse your mouth thoroughly with water and wait at least 15-20 minutes before taking a breathalyzer test. This will allow any lingering mouth alcohol to clear.

The trace amounts of alcohol from kombucha are metabolized quickly. However, sensitive EtG alcohol metabolite urine tests can detect markers for up to 80 hours after consumption, though levels from commercial kombucha are often below standard cutoffs.

Yes, 'hard kombucha' is significantly different. It is specifically brewed to have a higher alcohol content (often 3-8% ABV) and will cause a positive result on any standard alcohol drug or breath test.

Yes, other fermented foods, including sauerkraut, kefir, and even ripe bananas, contain trace amounts of alcohol as a natural byproduct of fermentation. These could also potentially trigger a highly sensitive test, though the amount is usually very low.