Self-Test for Breath Alcohol

Alcohol, Breath Test

What To Think About

A blood alcohol test is more accurate than a breath alcohol test. For more information, see the medical test Blood Alcohol.

Driving under the influence of alcohol (DUI) can be deadly. Alcohol is involved in nearly half of all fatal highway accidents. Even mild intoxication can impair your ability to drive safely. At 0.06 BAC, your judgment and physical coordination are impaired. At a BAC of 0.08, your muscle coordination and driving ability are significantly impaired.

How much alcohol it takes to raise your blood alcohol level depends on:

• The amount of alcohol you drink.
• How fast you drink the alcohol.
• Your weight.
• Your age.
• How fast your body breaks down (metabolizes) the alcohol. Different people metabolize alcohol at different rates.
• Your sex.
• The amount of food in your stomach when you drink.

Factors that affect how quickly the blood alcohol level rises in the body include:

• The number of drinks per hour. As you increase the number of drinks per hour, your blood alcohol level steadily increases.
• The strength of alcohol (proof or percentage) in the drink.
• Your weight. The more you weigh, the more water is present in your body, which dilutes the alcohol and lowers the blood alcohol level.
• Your sex. Women's bodies typically have less water and more fat than men's bodies. Alcohol does not go into fat cells as well as other cells, so women tend to retain more alcohol in their blood than men do. Also, a woman's hormones may affect the breakdown of alcohol.
• Your age. One drink raises the blood alcohol level of an older adult 20% more than it does for a young adult.
• The presence of food in your stomach. Food in the stomach absorbs some of the alcohol. The blood alcohol level will be higher if you do not eat before or during drinking.
• The kind of mixer used. When carbonated mixers (such as tonic water or club soda) are used, the body absorbs alcohol more quickly.
• Other medicines or drugs. A person who drinks alcohol and takes certain medicines, such as antihistamines or sedatives (tranquilizers), may feel more of the effects of alcohol. Also, a person who uses other drugs, such as marijuana, will feel the effects of both drugs more than if the drugs were used separately.

Effects of drinking alcohol

Having a measurable amount of alcohol in the blood can mean that judgment and reflexes are impaired.

Effects of drinking alcohol

Number of drinks per hour*	Estimated blood alcohol concentration (BAC)†	Observable effects†
1–2	0.02	Relaxation, slight body warmth
3	0.05	Sedation, slowed reaction time
6	0.10	Slurred speech, poor coordination, slowed thinking
12	0.20	Difficulty walking, double vision, nausea, vomiting
18	0.30	May pass out, tremors, memory loss, cool body temperature
24	0.40	Difficulty breathing, coma, possible death
30	0.50 and greater	Death
*1 drink = 1.5 fl oz (45 mL) liquor (80 proof) or one glass [5 fl oz (150 mL)] wine or one glass [12 fl oz (360 mL)] beer.
†BAC and the effects of drinking alcohol vary from person to person and depend upon body weight, the amount of food eaten while drinking, and each person's ability to tolerate alcohol.

You can buy breath alcohol tests on the Internet, either directly from the manufacturer or from a company that sells this kind of product. If you have access to the Internet, you can find this information by searching for the type of test or the name of the manufacturer.

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Author:	Jeannette Curtis	Last Updated: May 9, 2008
Medical Review:	Kathleen Romito, MD - Family Medicine R. Steven Tharratt, MD, MPVM, FACP, FCCP - Pulmonology, Critical Care, Medical Toxicology
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