Answer: Yes. If somebody has specific health issues or some medications, they can affect the results of the breath test. The breath test machine is attempting to measure a blood alcohol level from a breath sample. And what it does is when you blow into the tube, it will shoot an infrared beam through the tube. A molecule of alcohol will absorb a certain wavelength of the light and they will measure how much of that wavelength has been absorbed, and then they’ll figure out and calculate what your alcohol molecules are. There are other molecules that will mimic alcohol and also pull the same wavelength. A good example is a diabetic person. Diabetics tend to produce what is called a ketone. Ketones create alcohol in your body. The breath test machine cannot tell the naturally produced alcohol of a ketone from an ethyl alcohol molecule. Anorexics are another example of someone who is producing ketones. Their eating habits have them actually burning muscle in their body. There are certain medications that when it gets expelled through your breath can also absorb that molecule. So basically, you also have acid, acetone, acetaldehyde, toluene. Several things can affect the test.