False Breathalyzer Results are Caused by Many Common Things!

False breathalyzer results are caused by any of a number of things. (‘Breathalyzer’ has become generic for any alcohol breath testing device. But it’s actually a brand name.)


I.  Acetone

II. Summary

However, a major cause of false breathalyzer results is acetone in the breath.

I. Acetone

Acetone in the breath is one cause of false blood alcohol concentration (BAC) results from breathalyzers. Readings from such machines are actually only indirect estimates of BAC. In reality, only a sample of blood itself can yield a true measure of BAC.

Acetone exists in the breath of average people. And it can be high enough to cause false readings. Thus, it can cause conviction of innocent drivers.

Hypoglycemia is a significant cause of acetone in the breath. And diabetics can have levels of acetone in the breath high enough to get false readings of .06.


false breathalyzer resultsHypoglycemia also causes symptoms similar to intoxication. They include shakiness, dizziness, clumsiness, jerky movements, difficulty paying attention, and confusion.

The government (CDC) reports that 23.6 million people in the country have diabetes. And about 5.7 million of these don’t know they have the disease.

Other things can also cause hypoglycemia.

  • Conditions such as cardiac, kidney and liver diseases.
  • Aspirin in large doses, sulfa meds and pseudo ephedrine.
  • Overexertion, fright or anxiety.
  • Diet soda.

Either fasting or dieting can also cause much higher levels of acetone. Research has shown that fasting can increase the acetone level high enough to give a false reading of .06 BAC.


A low-carb diet can increase acetone levels. The body produces more acetone to compensate for the reduced glucose in the diet. The Atkins and similar diets seek low carb ketosis. This promotes the “burning” of fat.

Ketones create isopropyl alcohol. It turns into acetone. Thus, a side effect of ketosis is a high level of acetone. Machines can falsely measure acetone as alcohol. This can and does occur among teetotalers.

Such false readings are in addition to any other compounds in the methyl group. Over a hundred of these commonly occur in the human breath.

II. Summary: False Breathalyzer Results

In summary, acetone in the breath can cause false positive readings in breathalyzers. Hypoglycemia can cause people to fail field sobriety tests. It’s important to keep impaired and drunk drivers off the road. This protects public safety. But it’s also important to protect innocent drivers. They shouldn’t suffer for a crime they didn’t commit.

Perhaps convicting innocent drivers using false breathalyzer results should be a crime.

More on False Breathalyzer Results

Karch, S.  Forensic Issues in Alcohol Testing.  Boca Raton: CRC, 2008.