I’m A Diabetic. Will That Affect My Ignition Interlock Test?

If you have diabetes, you might be concerned about rumors that your condition can cause a false positive with an ignition interlock, resulting in a failed test and a possible lockout from your vehicle. If you believe this, you’ve fallen victim to one of the constant plagues of the Internet: the Outdated Information That Will Not Die.

The concern stems from acetone, a chemical produced in the body during ketosis, the process by which one’s body gets energy from burning fat. Diabetics and people on low-carbohydrate diets experience ketosis and thus produce acetone in their bodies.

The first ignition interlocks, produced in the 1980s, employed semiconductors to detect alcohol, and these devices were also sensitive to acetone. Thus, diabetics would sometimes get a false reading.

However, modern ignition interlock devices employ fuel cells, and not semiconductors, to detect alcohol. These advanced devices are able to distinguish between acetone and alcohol, and will not cause a false positive.

In the old days before fuel-cell technology, acetone was known as an interferent – a substance that would interfere with the alcohol-sensing reaction of the ignition interlock. Cigarette smoke was also considered an interferent.

The National Highway Traffic Safety Administration (NHTSA) does exhaustive tests on interlock devices, and the organization has determined that neither acetone from one’s body or cigarette smoke will skew tests (though it’s a good idea to wait a minute after taking a drag on a cigarette as smoke will shorten the life of the interlock’s sensor).

So, if the concern about diabetes and ignition interlocks comes up, consider yourself a mythbuster. Put the Outdated Information That Will Not Die to rest at all time. Your ignition interlock will keep you on the road, legally and safely, as long as you keep away from alcohol, the one substance that really does make the device do its job.