Blood Alcohol Test: About This Test

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Band tied tightly above elbow, with blood being drawn from vein at bend of elbow

What is it?

A blood alcohol test measures the amount of alcohol in the body. This measurement is called the blood alcohol concentration, or BAC.

The blood alcohol test measures only the amount of alcohol in the blood at the time the sample is taken. It does not show how long you've been drinking or whether you have an alcohol-use problem.

Why is this test done?

A test for blood alcohol level is done to:

  • Check the amount of alcohol in the blood if you are suspected of being legally drunk.
  • Find the cause of an altered state of mind, such as unclear thinking, confusion, or coma.

How is the test done?

A health professional uses a needle to take a blood sample, usually from the arm.

When should you call for help?

Call 911 anytime you think you may need emergency care. For example, call if:

  • You are very confused or can't think clearly.
  • You feel you cannot stop from hurting yourself or someone else.
  • You have a seizure.
  • You vomit blood or what looks like coffee grounds.

Where to get help 24 hours a day, 7 days a week

If you or someone you know talks about suicide, self-harm, a mental health crisis, a substance use crisis, or any other kind of emotional distress, get help right away. You can:

  • Call the Suicide and Crisis Lifeline at 988.
  • Call 1-800-273-TALK (1-800-273-8255).
  • Text HOME to 741741 to access the Crisis Text Line.

Consider saving these numbers in your phone.

Go to 988lifeline.org for more information or to chat online.

Call your doctor now or seek immediate medical care if:

  • You have new or worse symptoms of withdrawal, such as trembling, feeling restless, and sweating.
  • Your withdrawal symptoms come back after not bothering you for days or weeks.
  • You cannot stop vomiting.

Watch closely for changes in your health, and be sure to contact your doctor if:

  • You need help to stop drinking.

Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor if you are having problems. It's also a good idea to keep a list of the medicines you take. Ask your doctor when you can expect to have your test results.

Where can you learn more?

Go to http://www.healthwise.net/patientEd

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Current as of: November 15, 2023

Author: Ignite Healthwise, LLC Staff

Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

Current as of: November 15, 2023

Author: Ignite Healthwise, LLC Staff

Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

The Health Encyclopedia contains general health information. Not all treatments or services described are covered benefits for Kaiser Permanente members or offered as services by Kaiser Permanente. For a list of covered benefits, please refer to your Evidence of Coverage or Summary Plan Description. For recommended treatments, please consult with your health care provider.