DUI or Diabetes?

Was that person arrested for drunk driving truly under the influence of alcohol—or could it be that he was simply a diabetic having a low? The similarity in symptoms caused by alcohol intoxication and low blood glucose levels is striking and commonly leads to easy—but false—conclusions by law enforcement officers.

Diabetes is a very common disease in America. Fifteen to 20 percent of all drivers on the road are diabetics. The reactions of a person in the early stages of a low blood glucose attack include dizziness, blurred vision, slurred speech, weakness, loss of coordination and confusion. Coincidentally, these are the symptoms and signs that the patrol officer is looking for in a person who is driving under the influence of alcohol. And the officer’s observations are quickly followed by a failing performance on DUI field sobriety tests.

But a Breathalyzer Will Clear a Diabetic, Right?


Ignoring for the moment the inherent inaccuracy of these breath-alcohol machines, most suffer from a little-known design defect—they do not actually measure the alcohol in the blood. Rather, they use infrared beams of light. The light beams are absorbed by any chemical compound in the breath sample (including ethyl alcohol) that contains the “methyl group” in its molecular structure. The more absorption, the higher the blood-alcohol reading. The machine is programmed to assume that the compound is “probably” alcohol.

Unfortunately, thousands of compounds containing the methyl group can register as alcohol. One of these is acetone. And a well-documented byproduct of hyperglycemia is a state called ketoacidosis, which causes the production of acetones in the breath. In other words, the Breathalyzer will read significant levels of alcohol on a diabetic’s breath, where in fact there may be little or none at all.

Scientific Research Sides With Diabetic Drivers

In the September 2003 issue of Medical and Toxicological Information Review, John Arnold, MD, in a scientific article entitled “Hypoglycemia: Driving Under the Influence,” reports that:

Hypoglycemia (abnormally low levels of blood glucose) is frequently seen in connection with driving error on this nation’s roads and highways, including accidents with personal and material damage. Even more frequently are unjustified DUIs or DWIs stemming from hypoglycemic symptoms that can closely mimic those of a drunk driver.

Actually, you don’t even need to be a diabetic to display hypoglycemic-induced symptoms of intoxication. Perfectly normal, healthy individuals can experience temporary conditions of low blood glucose after consuming small amounts of alcohol, resulting in exaggerated but false symptoms of intoxication. Fasting glycemia can exist if a person has not eaten in 24 hours or has been on a low-carbohydrate diet. Production of glucose in the liver is stopped while the alcohol is broken down. Result: The blood glucose level will drop, affecting the central nervous system—and producing symptoms of a person who is under the influence of alcohol.

More Education on Diabetes Needed By the Law

Undoubtedly, thousands of diabetics have been falsely accused—and convicted—of drunk driving in the past because of nothing more than a physiological condition. Law enforcement, prosecutors and defense attorneys need to become educated about the false symptoms and breath readings associated with this condition.