How Long Does Alcohol Stay in Your System? Alcohol Half-Life

Alcohol is classified as a depressant because it slows down the central nervous system. After drinking, it quickly enters the bloodstream through the stomach and small intestine. How much is absorbed depends on factors like the amount consumed, body weight, and gender. In the U.S., alcohol misuse is a growing concern—about 27.9 million people ages 12 and older lived with Alcohol Use Disorder in 2024. If you or someone you care about is struggling, know that help is available, and learning how alcohol affects the body can be the first step toward recovery.

Our Alcohol Addiction Treatment Programs

Drinking too much? See how Arizona IOP can help.

Call Now

Get Help

How Long Does Alcohol Stay in Your System

The body processes alcohol in several ways, but on average, it breaks down at a rate of about 0.015g/100mL per hour. This lowers a person’s blood alcohol concentration (BAC) by roughly 0.015 each hour. For example, if someone has a BAC of 0.20, it could take close to 14 hours before their system is clear of alcohol.

Despite common myths, things like coffee, energy drinks, or a cold shower won’t speed up the process. Once alcohol is in the bloodstream, the body can only remove it naturally—through sweat, urine, and breath. Drinking heavily in a short time can overwhelm the body and lead to alcohol poisoning, which is dangerous and potentially life-threatening.

The length of time alcohol stays in your system depends on several factors, including:

Amount of Alcohol

Weight

Gender

Liver Function

Medications

Medical Conditions

Half-Life

The term half-life usually refers to the time it takes for half of a substance to leave the body. However, alcohol works a little differently. Instead of having a true half-life, ethanol is removed from the bloodstream at a steady, constant rate.

That rate of elimination isn’t the same for everyone—it can be influenced by several factors, including:

Weight

People with a higher body weight often process alcohol more slowly than those who are lighter. Because of this, alcohol can remain in their system for a longer period of time.

Gender

Women generally metabolize alcohol differently than men, which often means it stays in their system for a shorter amount of time.

Liver function

For individuals with liver damage, the body may process alcohol more slowly, causing it to remain in the system longer than usual.

Medications

Certain medications can interfere with how the body breaks down alcohol, which may cause it to stay in the system longer than normal.

1. Understand When Alcohol Leaves the System

Understanding how alcohol is eliminated from the body is important for many reasons. It can give people a clearer idea of how long alcohol may stay in their system, which is especially helpful when deciding whether it’s safe to drive. It can also guide individuals on when to take medications that might interact with alcohol, helping to reduce potential health risks.

2. Understand How Alcohol Affects the Body

It also helps people better understand how alcohol affects their body. For instance, someone who processes alcohol more quickly may feel its effects sooner and more intensely than a person whose body eliminates it at a slower rate.

3. Understand If It’s Safe to Drive

Finally, knowing how quickly alcohol is eliminated can give you a better estimate of how much may still be in your system at any given time. This can be especially important when deciding if it’s safe to drive or operate machinery after drinking.

If you’re concerned about how alcohol affects your body, reaching out to a doctor is a smart step. A healthcare professional can explain how alcohol is processed in your system and give you guidance that’s specific to your health and lifestyle.

How Long Will Alcohol Be Identified on a Drug Test

On average, alcohol can be detected in the body for different lengths of time depending on the type of test. It may show up in the blood for up to 6 hours, on the breath for 12–24 hours, in urine and saliva for about 12–24 hours, and in hair for as long as 90 days.

Urine Test

If you’ve ever wondered, “how long does alcohol stay in your system?”, urine testing is one of the most common methods used to find out. These tests detect alcohol or its byproducts in the body. After drinking, the liver breaks alcohol down into a compound called ethyl glucuronide (EtG), which can remain in urine for up to 80 hours.

The process is simple: a small urine sample is collected and analyzed for alcohol or EtG levels. Typically, alcohol itself can be detected in urine for about 10 to 12 hours after drinking, while EtG extends the detection window significantly.

Breathalyzer

If you’re trying to understand how long alcohol stays in your system, it’s helpful to know about breathalyzer tests. A breathalyzer is a device that measures the amount of alcohol in your breath and is commonly used by law enforcement to check for impaired driving. Healthcare providers may also use breath tests as part of diagnosing alcohol-related issues.

During the test, you simply blow into a mouthpiece, and the device calculates your blood alcohol concentration (BAC) based on the alcohol detected in your breath. BAC reflects the level of alcohol in the bloodstream, and in most states, the legal limit for driving is 0.08% or higher.

Breathalyzer results are usually reliable for 12 to 24 hours after drinking. In some cases, alcohol may still be detectable on the breath for up to 48 hours, even if you no longer feel its effects.

Blood Test

A blood test is one of the most accurate ways to measure alcohol levels in the body. Law enforcement often uses it to confirm impaired driving, while doctors may order it to help diagnose or monitor alcohol use disorder.

During the test, a healthcare professional draws a small blood sample, which is then analyzed in a lab. Results are usually ready within a few hours and provide a clear picture of a person’s blood alcohol concentration (BAC).

If you’re wondering how long alcohol stays in your blood, the body typically processes it at a steady rate of about 0.015 g/100mL per hour. This means your BAC generally drops by 0.015 every hour until the alcohol is fully eliminated.

Wondering if you have alcoholism? Take the Quiz

Am I an Alcoholic?

Get Help for Alcoholism at Arizona IOP

Alcohol addiction is a serious challenge, but it is also treatable. If you’re struggling, know that you don’t have to face it alone—help and support are available. With the right treatment, it’s possible to take back control of your life and work toward lasting recovery.

At Arizona IOP in Scottsdale, Arizona, we offer personalized outpatient treatment programs designed to fit your lifestyle while still providing high-quality care. Our team of professionals uses evidence-based therapies, flexible scheduling, and compassionate support so you can heal without putting your life on hold.

Recovery is possible, and every step you take matters. If you’re ready to make a change, reach out to our Scottsdale team at Arizona IOP today. We’re here to guide you with the tools, care, and encouragement you need to build a healthier, sober future.

Other Drug Detection Times

If you’re asking, “how long does cocaine stay in your system?”, the answer depends on a few factors. In most cases, cocaine can be detected in urine for about 2 to 4 days after use. However, its metabolites—substances your body creates as it breaks down the drug—can remain detectable for much longer, sometimes up to several weeks.

The exact detection window varies from person to person and is influenced by things like how much was used, how often, individual metabolism, and overall health.

The answer to the question “how long does ecstasy stay in your system” is that Ecstasy, also known as MDMA, can usually be detected for about 2 to 4 days after use. During this time, traces of the drug may show up in urine, blood, or saliva tests. However, the exact length of time MDMA stays in your body depends on several factors, such as your metabolism, overall health, and how much of the drug you used.

The answer to the question “how long does heroin stay in your system” is that heroin is usually detectable for about 2 to 3 days after use. During this period, it may show up in urine, blood, or saliva tests. However, the exact detection window can vary depending on factors such as how much heroin was taken, how often it is used, and an individual’s metabolism and overall health.

The answer to the question “how long does meth stay in your system” is that methamphetamine, or meth, is usually detectable for about 2 to 4 days after use, though in some cases it may be found for up to a week. The exact duration depends on factors such as the amount used, frequency of use, individual metabolism, and the type of drug test being administered.

The answer to the question “how long does Xanax stay in your system” is that Xanax (alprazolam), a medication prescribed for anxiety and panic disorders, typically remains detectable for about up to 4 days after use. This means it may be found in your urine, blood, or saliva during this time. However, detection windows can vary depending on factors like dosage, frequency of use, your metabolism, and the type of drug test being used.

The answer to the question “how long does Suboxone stay in your system?” can vary. Suboxone, which contains buprenorphine and naloxone, may be detectable in urine tests for up to several days, and in some cases even longer, depending on factors like dosage, frequency of use, and your metabolism. Naloxone, one of its ingredients, leaves the body more quickly—usually within about 24 hours. Buprenorphine, however, can remain in the system for several days and may be picked up by different types of drug tests.

The answer to the question “how long does fentanyl stay in your system?” is that fentanyl and its metabolites are typically detectable in urine for about 1 to 2 days after use. However, the detection window can vary based on several factors, including the dosage, frequency of use, metabolism, and the type of drug test being used. In some cases, traces of fentanyl may be found for a slightly longer period.

The answer to the question “how long do opioids stay in your system” depends on several factors, including the type of opioid, dosage, frequency of use, metabolism, and the drug test used. In general, opioids can be detected in urine for about 2 to 4 days after use. However, some opioids with longer half-lives—such as methadone or buprenorphine—may remain detectable for a longer period.

The answer to the question “how long does weed stay in your system” is that marijuana can remain detectable for varying lengths of time depending on frequency of use, dosage, and metabolism. For occasional users, it may only be detectable for a few days to a week. However, for frequent or heavy users, marijuana can be detected in urine for up to 30 days or longer.

The answer to the question “how long does Ambien stay in your system” is that Ambien (zolpidem) generally stays in your body for about 8 hours, with its sedative effects wearing off after that period. However, it can still be detectable in urine for up to 72 hours after use. The exact duration depends on factors like your dosage, how often you use it, and your metabolism.

The answer to the question “how long does methadone stay in your system” is that methadone can usually be detected in urine for 7 to 10 days after the last dose. However, the exact length of time depends on factors like your metabolism, dosage, and how often you use it. In some cases, methadone may also be detectable in hair follicles for several months.

The answer to the question “how long does Percocet stay in your system” is that Percocet can usually be detected in urine for about 3 to 4 days after the last dose. The exact detection window can vary based on factors such as your metabolism, the dosage taken, and the type of drug test used.