Blood Alcohol Test

There is a legal blood alcohol level for driving. If you exceed the drink-and-drive limit, you can be penalized for a criminal offense. The blood alcohol level is the level of alcohol in your blood. A blood alcohol test measures the amount of alcohol in the body. If you want to know more about blood alcohol tests, keep reading this article.

What Is a Blood Alcohol Test?

A blood alcohol test will measure the amount of alcohol present in your blood sample. In case you have been drinking alcoholic beverages, you will have alcohol content in your blood.

Ethanol is the primary content of alcoholic drinks, such as distilled spirits, wine, and beer. When you drink alcohol, it gets easily absorbed by the body. The liver will then break it down for the body to get rid of it. Intoxication by alcohol can affect how the brain works. At first, you might feel no inhibition and talk more than usual. When the alcohol levels increase, you might not be able to think clearly.

Keeping on drinking even after being intoxicated can lead to alcohol overdose. Symptoms are trouble breathing, vomiting, and passing out. Overdose can also lead to death.

Only a few blood tests can measure if a person has been drinking. The BAC test is commonly used to learn if a person has drunk alcohol recently. BAC alcohol meaning is blood alcohol concentration. The test can find alcohol in the blood even after 12 hours of drinking. It can show the amount of alcohol you have had.

BAC range is not the only test for alcohol. Other blood tests can measure the alcohol that can stay in your blood for several weeks after you have had it. The tests are primarily used for testing alcohol use disorder or for checking if someone is recovering from AUD.

What Is the Purpose of a Blood Alcohol Test?

A blood alcohol test might be used for different purposes. Let’s take a look at them.

A legal reason might be the suspicion of a police offer that you are drinking and driving or driving under influence. Also, drug testing and alcohol testing is common after a car crash. Alcohol testing is done after a car crash to find out if it has played a role in the accident and if the legal limit of blood alcohol content is higher than usual.

Generally, you are asked to take a breath alcohol test on the spot. In case you refuse, you might be asked to get a blood alcohol test done. The BAC alcohol legal limit is used to penalize those who are indulging in underage drinking.

2.  Medical Reason

When you arrive at the ER or hospital confused, passed out, and showing signs of heavy drinking, you might be asked for a blood alcohol test. It helps a doctor to understand what is happening and how they can take care of you. Often, doctors perform a breath analyzer test but they might also draw your blood. The test use BAC test to diagnose alcohol poisoning, a possibly life-threatening complication of intaking a large amount of alcohol within a short period.

3.  Workplace Reason

You might also be asked to take one of these alcohol or drug tests randomly by the employer. They can make you take the test before hiring you. In case you have been in a work accident, you might be tested to learn if alcohol had been involved. Apart from a blood test, a saliva and urine test can also be done. A blood test will show if you have a normal blood alcohol level range or higher.

What Does a Blood Alcohol Test Measure?

An alcohol test measures the number of biomarkers, alcohol, or metabolites in a person’s serum or blood. The serum is the blood’s liquid part, which stays back after blood clots. Alcohol metabolites are created when they break down the particles of alcohol to get rid of it. A biomarker is an element that is present just after alcohol consumption.

The most popular way to measure alcohol use is to find out the amount of alcohol present in the blood of a person. Once you consume alcohol, it will stay in your body until broken down, mainly by the liver. If you drink faster than your liver can break download alcohol, your BAC will increase.

The test can also measure alcohol metabolites range to detect chronic alcohol use or relapse after a period of being sober. Multiple alcohol biomarkers can be found in blood, including;

1.  Phosphatidylethanol

The level of Phosphatidylethanol is aligned closely with the amount of alcohol someone consumes. The test is primarily used in research/

2.  Carbohydrate-Deficient Transferrin

CDT can help doctors identify heavy usage of alcohol. A raised CDT level suggests that an individual might be consuming over 50-80 grams of alcohol. This is equivalent to 3-6 drinks, per day for 2-3 weeks.

Alcohol Blood Test Percentage Result

Additionally, ethyl sulfate and ethyl glucuronide are alcohol metabolites that are measured in blood. Even though Etg/EtS can detect the presence of alcohol much longer than ethanol testing.  But this testing doesn’t indicate the frequency of alcohol consumption.

Blood alcohol level results might be given in different ways that include the percentage of BAC. The typical results are given below;

  •       Legally Intoxicated: 0.08% BAC.
  •       Sober: 0.0% BAC.
  •       At Risk for Serious Complications: Above .40% BAC. At this level, you might be at risk of death or coma.
  •       Very Impaired: 0.08%-0.40% BAC. At this level, you might have trouble speaking or walking. Other symptoms are nausea, confusion, and drowsiness.

Keep in mind that the timing of the test can have an impact on the result’s accuracy. A blood alcohol test can only be accurate within 6-12 hours after you have taken your last drink. In case you have any concerns or questions about the results, you can talk to a lawyer or a healthcare provider.

How to Interpret Results of the Blood Alcohol Range Test?

The outcome of the alcohol blood test can be reported in different ways, based on the type of alcohol blood test that is being performed.

For testing which determines the BAC of a person, the amount of alcohol in the blood is reported as a percentage or number.  If it is reported as a number, the test report will show the milligrams of ethanol per deciliter of blood. But if it is given in percentage, the alcohol concentration in the blood is reported as the percentage of alcohol in the blood of the person.

positive BAC test result shows that alcohol has been detected. But a negative test result shows that alcohol wasn’t detected at the time of the test. A negative test result shows that an individual has not taken alcohol within the detection window. It can also mean that the alcohol level in the blood didn’t meet the cut-off value of the lab for a positive result. However, a negative outcome doesn’t mean that a person has never consumed alcohol.

The impact of alcohol on a person depends on various factors, including how often or how much alcohol is consumed. It can also detect the person’s health, age, and family history. Since the tolerance for alcohol increased, chronic users tend to function normally even after consuming alcohol in higher amounts as alcohol metabolizes faster in them.

What to Expect During Blood Alcohol Content Test?

You might experience the following during the alcohol blood test;

  •       Your healthcare provider will check your arms for an accessible vein. It is an inner part of the arm on the other side of your elbow.
  •       When they have located the brain, they are going to clean and disinfect the area.
  •       Thereafter, they are going to insert a needle into the vein to take a blood sample.
  •       After the needle is inserted, a little blood might be seen in the test tube.
  •       If the lab has enough blood to perform the test, they are going to take out a needle and place a cotton ball to stop the bleeding.
  •       They are going to place the bandage over the site.

The whole process will take less than 5 minutes.

What Has to Be Done before Taking a BAC Range Alcohol Blood Test?

The test needs a blood sample. But you don’t need to take any special preparation for the blood alcohol test. In case you are taking any substances or medications that contain alcohol, you should tell your healthcare providers. This is because these substances can lead to the positive alcohol test result.


Even though the test is not accurate 100% of the time, blood alcohol tests are the most accurate process to find out the amount of alcohol present in an individual’s body. Even though it is the most accurate testing method, a sample of a person’s hair, sweat, saliva, breath, and urine can also be used for testing. A test can be performed for different purposes, including legal reasons, workplace drug testing, and medical reasons. It can also prove to be important for monitoring alcohol use problems.


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