How long does alcohol stay in your system? It depends on the type of test. Alcohol can usually be found in blood for up to about 12 hours and on the breath for about 12 to 24 hours, while urine tests that look for alcohol byproducts can detect drinking for up to about 5 days after heavy use. Hair tests can show alcohol use for up to about 90 days.
Your body can only break down alcohol at a steady, limited pace, and nothing you do can speed that up. Below, we explain how alcohol is processed, how long each type of test can detect it, and the factors that make a difference from person to person.
How Your Body Processes Alcohol
After you take a drink, alcohol is absorbed through your stomach and small intestine into your bloodstream. According to Cleveland Clinic, it takes around 60 to 90 minutes for alcohol to reach its peak level in the blood.
Most of the work of breaking down alcohol happens in the liver. The National Institute on Alcohol Abuse and Alcoholism (NIAAA) explains that an enzyme called alcohol dehydrogenase (ADH) turns alcohol into acetaldehyde, a toxic substance and known carcinogen. A second enzyme, aldehyde dehydrogenase (ALDH), then breaks acetaldehyde down into a less harmful substance called acetate.
Why You Cannot Rush It
Alcohol is cleared at a fairly constant rate. A StatPearls review of drug kinetics explains that the liver enzyme that breaks down alcohol becomes saturated even at moderate blood alcohol levels, so the body removes a fixed amount over time no matter how much you drank. In simple terms, the more you drink, the longer it takes to clear.
That is also why common “sobering up” tricks do not work. NIAAA warns that cold showers, hot coffee and walking do not reverse the effects of too much alcohol and could make things worse. Cleveland Clinic adds that caffeine will not clear alcohol from your system any faster.
How Long Does Alcohol Stay in Your System by Test Type?
Different tests look for different things. Some measure alcohol itself, which leaves the body fairly quickly. Others look for byproducts, called metabolites, that stay around much longer. Here are general detection windows from medical sources:
- Blood: MedlinePlus notes that a blood alcohol test can detect alcohol for up to about 12 hours after your last drink.
- Breath: Breathalyzer tests can detect alcohol for about 12 to 24 hours, according to Cleveland Clinic.
- Urine (EtG and EtS tests): These tests look for ethyl glucuronide and ethyl sulfate, which the body makes when it processes alcohol. A 2018 review of alcohol biomarkers reports that EtG can be detected in urine for up to about 24 hours even after small amounts of alcohol, and for up to 130 hours (a little over 5 days) after heavy drinking.
- Blood (PEth test): Phosphatidylethanol, or PEth, forms only when alcohol is present. The same review notes it can be detected for up to 12 days after a single drinking occasion.
- Hair: Cleveland Clinic says hair testing can detect alcohol up to 90 days after a person stops drinking, and the 2018 review notes hair testing can look back over several months.
So, how long does alcohol stay in your system for your situation? These are general ranges, not guarantees. The exact window depends on how much you drank, over how long, and your own body.
Factors That Affect How Long Alcohol Lasts
Two people can drink the same amount and have very different blood alcohol levels. Cleveland Clinic and NIAAA point to several factors:
- How much you drink: Because alcohol is cleared at a steady rate, more drinks means more time to clear.
- Sex: Women generally take longer to process alcohol.
- Age: Processing tends to slow as you get older.
- Body size: Smaller people tend to reach higher blood alcohol levels from the same amount.
- Genetics: NIAAA notes that differences in the enzymes that break down alcohol affect how quickly it is processed.
- Medications and health conditions: Some medicines and problems with the liver, kidneys or stomach can change how alcohol is handled.
Eating food may affect how you feel while drinking, but Cleveland Clinic notes it will not change how soon you can pass an alcohol test.
What Blood Alcohol Levels Mean
Blood alcohol concentration (BAC) is the percentage of alcohol in your blood. MedlinePlus explains that the legal limit for driving is usually 0.08%, and describes how effects grow as BAC rises:
- 0.01% to 0.05%: Feeling relaxed and less alert, with a slight loss of judgment.
- 0.06% to 0.15%: Slurred speech, reduced coordination and impaired judgment, memory or balance.
- 0.16% to 0.30%: Trouble walking and speaking, drowsiness, confusion, nausea and memory blackouts.
- 0.31% and higher: Especially dangerous levels that may be fatal.
High BAC levels often come from drinking a lot in a short time. Our article on binge drinking explains why this pattern is risky.
When Alcohol in Your System Becomes an Emergency
NIAAA also warns that blood alcohol can keep rising even after a person stops drinking or passes out, because alcohol still in the stomach and intestines continues to enter the bloodstream. Signs of alcohol overdose include:
- Confusion or stupor
- Trouble staying conscious, or not being able to wake up
- Vomiting or seizures
- Slow or irregular breathing
- Slow heart rate and clammy skin
- Very low body temperature, bluish skin or paleness
If you think someone has an alcohol overdose, call 911 right away. Do not wait for all the signs to appear. Mixing alcohol with other drugs raises the danger even more. Learn about the risks of mixing benzodiazepines and alcohol.
Frequently Asked Questions
How long does one drink stay in your system?
It varies by person and by test. Blood tests usually detect alcohol for up to about 12 hours, while EtG urine tests can pick up even small amounts for up to about 24 hours.
Can I flush alcohol out of my system faster?
No. Coffee, cold showers and walking do not speed up how fast your liver breaks down alcohol. Only time clears it.
Why would a treatment program test for alcohol?
MedlinePlus notes that treatment programs may use alcohol tests to monitor sobriety. Testing is meant to support recovery and safety, not to punish.
What if I feel sick when alcohol leaves my system?
Shakiness, sweating, anxiety or trouble sleeping as alcohol wears off can be signs of withdrawal and physical dependence. Alcohol withdrawal can be life-threatening and needs medical supervision. Read our alcohol withdrawal timeline to learn more.
Get Help for Alcohol Use in Lancaster, PA
If you often find yourself asking how long does alcohol stay in your system before work or a test, it may be a good time to look at your drinking more closely. Our guide to the signs of alcoholism can help. The Ranch Pennsylvania Outpatient Services offers addiction treatment programs in Lancaster, including a partial hospitalization program and an intensive outpatient program. Explore our alcohol addiction resources or verify your insurance today. Our admissions team is available 24/7, and calls are free and confidential.
