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What Factors Can Influence Your BAC Level?


A high blood alcohol or BAC level often equals a citation for DUI or more stringent punishment depending on the number of times you’ve been convicted. So, it implies that the best way to avoid a conviction for driving under the influence is to keep your BAC (blood alcohol concentration) below the legal limit. In Idaho, the BAC level is 0.08%.

While it is an accepted fact that most drivers arrested for DUI were most likely intoxicated, it is not always because of excessive alcohol consumption. It means that you could be intoxicated without consuming alcohol or after your BAC should ordinarily have been reduced. This is known as “rising blood alcohol,” which is a legal defense to a DUI charge.

This article introduces you to factors that could increase your BAC level even without drinking or hours after you did. If you get arrested for driving under the influence, contact our DUI attorneys. We will provide you with excellent legal advice and defense.

How Does Alcohol Affect Brain Function?

The first thing to know about alcohol is that it is a generic term for ethanol. The latter produces intoxication because of the depressive effects it has on the brain. This effect affects both the physical and mental functions of the person intoxicated. The preceding happens progressively as you consume more alcohol.

Thus, the higher the BAC, the more out-of-character you’ll ultimately suffer from euphoria IQ, poor judgment, confusion, and disorientation, etc. When this happens, and you get behind a wheel, you’ll likely get into an auto crash. If the latter occurs, you’ll face severe punishments. The only way out is to put up a strong defense, one of which is rising blood alcohol.

What Factors Affect the BAC Level?

Generally, after reaching a rapid peak 30 minutes to two hours after consuming alcohol, BAC starts declining at a gradual rate. However, it doesn’t always work this way as several factors cause rising alcohol levels. They include:

  • Whether you consumed the alcohol on a full or empty stomach
  • The types of alcohol consumed, e.g., beer versus hard liquor
  • Your sex
  • The rate at which you consumed the alcohol that is, quickly or slowly
  • Your functional tolerance for alcohol
  • Interaction with drugs or illnesses
  • Fatigue

Can I Have a High BAC Level Without Consuming Alcohol?

Aside from the factors discussed above, it is possible to experience rising blood alcohol levels without consuming alcohol. This is due to a medical condition known as auto-brewery syndrome. It is also referred to as gut fermentation syndrome or endogenous ethanol fermentation.

The condition makes you drunk without consuming alcohol. This happens when the body turns sugary, starchy foods (carbohydrates) into alcohol. The ailment is hard to diagnose and often gets confused with other medical conditions.

Note that very few people get diagnosed with this ailment. But if you do, you can have over and above the blood alcohol concentration. The good news is even if the police arrest you, you will likely not get charged if you can prove you have auto-brewery syndrome.

The illness is a legitimate defense to a DUI charge. However, you have to present medical evidence showing you have the ailment. So, you can’t drink and hope to use the auto-brewery syndrome as a defense. But if you think you do, contact a DUI lawyer, and they’ll help you arrange to get tested.

Do You Need Expert Evidence When Using Rising Blood Alcohol Defense?

The simple direct answer is YES. Claiming you did not drink or you drank so long ago that your BAC should have dropped is not enough to get you off a DUI charge. Since you assert the existence of a factor outside the standard chemical tests for determining legal intoxication, the onus is on you to prove the existence.

This is where a DUI defense expert witness comes in. The preceding could be your diagnostic physician or a forensic toxicologist. The toxicologist’s job is to prove that BAC levels can keep rising by constructing a personal BAC timeline. If the court accepts the expert evidence, your DUI lawyer can ask them to dismiss your case before trial. Should the case go to trial, the testimony would cast reasonable doubt.

Charged With a DUI in Boise, Idaho? Let Our Expert DUI Attorneys Help You!

Facing a DUI charge is never easy. It’s harder when you know you didn’t drink or shouldn’t have a high BAC level. Thankfully, you can beat the charges and have your case dismissed by working with our expert DUI lawyers at the Trilogy Law Group. We will do all the work to get you off the unfair charges, so call us today to schedule a free consultation.