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Denver Criminal Lawyer Explains Factors That Could Affect Your Breathalyzer Test

March 1, 2017

Breathalyzer devices are used to test drivers’ blood alcohol content. If a driver has a blood alcohol content, or BAC, above 0.08%, he is over the legal limit and can be arrested for driving under the influence of alcohol. In Colorado, a driver can be arrested for the lesser charge of driving while ability impaired if their BAC is above 0.05%. But, according to Denver criminal defense lawyer John Buckley, these tests are not always accurate. Here are a few of the factors that could affect your breathalyzer reading:


There are certain medications that could impact your reading and make it seem as if you are under the influence of alcohol, even if you haven’t had a drink all night. Some medications that are used to treat cold or canker sores contain up to 70% alcohol, which will impact a breathalyzer reading. Cold and sleep medicines also contain alcohol, although not as much as cold and canker sore medications. But, any amount of alcohol could impact your test, so you should avoid taking any medications before getting behind the wheel.


In order to function properly, breathalyzer devices need to be calibrated on a regular basis. If a police officer fails to calibrate the device correctly, the reading may or may not be accurate. Learn more about recent news, Colorado’s breathalyzers being called into question.

Health Conditions

Certain health conditions can also affect your breathalyzer reading. For example, if you have diabetes, you probably have much higher levels of acetone than someone without diabetes. Unfortunately, older breathalyzer devices were not designed to differentiate between ethyl alcohol and alcohol that has been consumed. If you have diabetes, it’s possible you would blow above 0.08% on an older machine.

Research has also shown that people with gastroesophageal reflux disease (GERD) should be wary of breathalyzer results. People who suffer from GERD may blow above the legal limit even if they are not impaired and have only had a small amount of alcohol.

If you are asked to blow into the breathalyzer, you will have to blow for 4-5 seconds and provide about 1.5 liters of air. But, people who suffer from asthma, emphysema or any other serious respiratory condition may find it difficult to do this.

Breath Fresheners

Are you meeting a date for dinner? You may want to think twice about taking a swig of mouthwash or popping a mint in your mouth before you get behind the wheel. Mouthwash has a lot of alcohol that could linger in your mouth and affect your breathalyzer test. Some mints, gums, and cough drops also contain alcohol that could impact your reading, so all of these items should be avoided if you want to protect yourself from a false positive test.

There are many other factors, such as human error, that could affect the results of your breathalyzer test. If you believe your breathalyzer test wasn’t accurate, you will need an attorney to handle your DUI case. Contact the Law Office of John Buckley immediately following your arrest for driving under the influence. We work tirelessly to defend your rights and ensure you receive the best legal representation possible. Contact John L. Buckley as soon as possible to schedule a legal consultation.