How long does alcohol stay in your system?
Alcohol stay in your system and can be detected in urine up to 24 hours after you end a drinking session. So how long does alcohol stay in the body, urine, breath, saliva and blood? We review alcohol metabolism, alcohol detection, alcohol addictive properties, and drug testing principles for alcohol below.
Peak levels and half life of alcohol
One serving of alcohol is fully absorbed into the blood stream within 30 minutes to 2 hours after intake. This is because the body can metabolize about 0.25 ounces of alcohol per hour. However, the effects of alcohol vary by individual and by how much alcohol they drink in one session. In fact, the effects and levels of alcohol in the body depend upon a number of factors:
- a person’s size and weight
- individual metabolism rate
- related food intake
- the beverage consumed
Generally speaking, alcohol is absorbed into the blood relatively quickly and metabolized more slowly. In an average 150 pound person, for example, each drink adds 0.02% to BAC and hour that passes removes 0.01% from it. This is why alcohol concentrations build steadily throughout a drinking session.
Why test for alcohol?
Alcohol impairment within the workplace and while driving can cause drowsiness, loss of concentration, memory loss, impaired judgment, distortion of reality, poor coordination and slow reaction time. People who drink alcoholic beverages while at work or while driving put themselves and everyone around them in danger. Local, state and federal laws have been created to protect public safety and require that you submit to an alcohol test when requested by employers or law enforcement officials. How long do states keep a DUI on your record? It depends on that state’s laws.
Alcohol drug testing methods
1. Urine based tests – Alcohol has a relatively short lifespan in the human system. Urine testing can be an accurate and reliable method for detecting the presence of alcohol if performed within the relatively short period following ingestion in which it can be detected. The results of a urine ethanol assay are expressed qualitatively as either “positive” or “negative” and do not measure levels of intoxication.
2. Blood based tests – Blood testing for alcohol, on the other hand can measure the amount of ethanol in blood (which requires a 4 ml specimen in a fluoride-oxalate container) and is the preferred test in chronic alcoholism or in an acutely intoxicated patient.
3. Breathalyzer tests – In addition to urine and blood sample testing, ethyl alcohol is measured by a gas chromatographic procedure which is able to differentiate it from other alcohols, notably methanol and isopropanol. In fact, today most drug screens for alcohol are taken via breathalyzer tests. Breath and tests are more useful to determine both the presence and the degree of acute alcohol intoxication. Because breath tests are much simpler, faster and are less invasive than blood tests, they are the most common alcohol testing method used to detect the presence and amount of alcohol consumed.
How long does alcohol stay in the body?
Alcohol has an approximate detection time of 12-24 hours in urine. However, the detection time for alcohol depends upon the maximum level of blood alcohol content (BAC) achieved and varies by individual. People who achieve a moderate level of intoxication (0.10% BAC) are detectable about 8 hours after achieving that level.
Alcohol, alcoholism and addiction
The chronic use of alcohol over time can cause physical and mental dependence on alcohol in order to function. Signs of alcoholism include craving, withdrawal when you stop drinking or cut back on drinking, and tolerance (the need to drink more to get the same effect). About 10% of drinkers can develop psychological and physical dependency on alcohol. But help for alcoholism is available. Once you go through medically supervised alcohol detox and withdrawal to get alcohol out of your body (can you die from alcohol withdrawal?), you learn ways to cope with life without drinking. Yes. Recovery from alcoholism is difficult. But it’s possible.
Problems with alcohol?
If you think that you may have problems with alcohol, you probably do. If you are continually testing positive for the presence of alcohol, or routinely arrested for DUIs…it may be time to ask for help. Please leave your questions about drinking alcohol and alcohol detection below. Or, if you think you may have a drinking problem, please let us know anonymously. We are here to help refer you to local resources and services.
Reference sources: SAMHSA/CSAT Treatment Improvement Protocols: Chapter 9, Drug Testing as a Tool
U.S. Department of the Interior Signs and Symptoms Fact Sheet on Drugs and Alcohol
U.S. Department of Transportation publication: Safety issues on drugs and alcohol
U.S. National Criminal Justice Reference Service (NCJRS) publication Drug testing in a drug court environment: common issues to address
About 10% of drinkers can develop psychological and physical dependency on alcohol.
Photo credit: SnaPsi Stalker