How Long Does Alcohol Stay in Your System? Test Methods and Timeframes
How long alcohol stays in your system can depend on a number of different factors. A normal concern that many people have after a heavy night of drinking is how soon they will be able to drive safely the following day.
On average, the human body can process one unit of alcohol per hour. However, this can vary from person to person. Other factors, including age, gender, medications, body composition, and organ health, can all affect how long alcohol stays in your system.
One particular factor that can slow down the rate at which you process alcohol is how much you drink. For example, someone who binge drinks will have a backlog of units that the liver needs to process. Liver health is also an important component of your body’s ability to flush out alcohol.
Additionally, a person who is alcohol dependent will always have some level of alcohol in their system in order to prevent alcohol withdrawal symptoms from developing. We will examine these additional factors further on.
Tests Commonly Used To Detect The Presence of Alcohol In Your System
There are a number of tests that are commonly used to detect the presence of alcohol in your system.
Alcohol Breath Test – Breathalyzers
The most commonly used method is a breathalyzer. Breathalysers are machines that measure alcohol levels in your breath. Any number that registers above 0.02% is deemed unsafe for driving, as this amount affects your visual functioning, response times and judgement.
Breathalyzers are the most widely utilised testing device by law and other organisations to identify the recent consumption of alcohol. As there is still residual alcohol present in the body that has not been completely metabolized, breathalyser tests can detect traces of alcohol up to 24 hours after drinking.
Blood Test For Alcohol
Following a positive breath test, a person will then be taken for a blood sample to gain an accurate reading of blood alcohol content (BAC). These results will determine if prosecution is viable or not.
Blood tests for alcohol are normally only taken when there is sufficient reason to suspect a person has been drinking. Blood alcohol tests are the most accurate way of measuring the amount of alcohol in your body. However, they are not practical, take time to process and need to be carried out by a trained medical professional.
Urine Sample Tests For Alcohol
Urine sample tests are also another used method that detects a wide variety of substances. These are mostly used by companies, drug and alcohol services and private treatment facilities. However, in the case of alcohol, these tests are only used when no other more suitable testing device is available. This is because whilst urine samples can detect the presence of alcohol, they cannot determine an accurate blood alcohol concentration level or exactly when alcohol was consumed.
Mouth Swab Sample Tests For Alcohol
Saliva tests use a strip or a swap to take a sample of saliva from a person’s mouth. Saliva tests can be used to detect a number of different substances and provide quick results. The accuracy of a mouth swab drug test, when administered correctly, is estimated to be 97.5%. Saliva tests are helpful in identifying recent alcohol consumption, but like urine tests, they cannot determine the amount.
More recently, ankle bracelets ‘Sobriety tags’ are being fitted to alcohol-related offenders. These bracelets detect the presence of alcohol around the clock in a person’s sweat and measure their BAC. Offenders who are released from prison on an alcohol abstinence order can be prosecuted and returned to prison if alcohol consumption is detected in their system.
How The Body Processes Alcohol
Before looking at the detection times for how long alcohol stays in your system, it is important to understand how the body metabolises alcohol and how personal factors can impact this.
When alcohol is consumed, approximately 20% of it is rapidly absorbed into the bloodstream through the stomach, with the remaining 80% being absorbed by the small intestines. Alcohol then travels quickly through your bloodstream, affecting your brain first, then your kidneys, lungs and liver, where it is broken down and processed. Any alcohol that is not metabolized exits the body through sweat, urine and saliva.
When someone drinks a lot of alcohol over a short space of time (binge drinking), the liver cannot process alcohol at the same rate, so it remains in the body for much longer than a single unit or ounce would. This raises a person’s blood alcohol content (BAC), making them feel the effects of alcohol for longer and, in a more prominent way.
The Effects Of Alcohol Can Be Varied But Include:
- Slurred speech
- Nausea and vomiting
- Impaired decision-making and judgement
- Reduced inhibitions
- Memory problems
- Changes to blood pressure, heart rate and respiratory rate
- Reduced coordination
- Loss of consciousness
When a person binge drinks, they are at risk of alcohol poisoning, accidents, altercations, not being in control of their actions, risk-taking and even death.
How Long Does Alcohol Stay In Your System: Blood, Breath, Sweat & Urine?
Determining exactly how long alcohol is detectable in your system depends on many variables, including which kind of drug test is being used. Different tests have different time frames of detection, not just when it comes to detecting alcohol but for other substances also.
- Blood: Alcohol can stay detectable in your bloodstream by a blood test for up to 12 hours post-consumption
- Urine: The ethyl glucuronide (EtG) test can detect alcohol in urine for up to 3 to 5 days, while the traditional method can detect it for 10 to 12 hours.
- Hair: Like most substances, alcohol can be detected in a hair follicle drug test for up to 90 days or more
- Saliva: Alcohol can be detected in your saliva for 12-24 hours after drinking
- Sweat: Sweat tests are not commonly used unless for a sobriety tag. They can detect the immediate presence of alcohol in sweat shortly after you drink but can further detect alcohol for up to 4 weeks in heavy drinkers
Detection times for how long alcohol stays in your system are guidelines and not exact. This is due to the variables that can affect a person, how accurately the test is administered, and the type and make of the test.
Factors That Affect How Long Alcohol Stays In Your System
Variations that determine how long alcohol stays in your system affect everyone. Genetically, everyone is unique, and whilst other variations can be minor, they can all play a part in how efficiently (quickly) your body processes alcohol.
Factors That Affect The Rate Your Body Processes Alcohol
- Liver health and general health
- Medications and drugs that are taken with alcohol
- Metabolic rate
- Frequency of use
- Amount of alcohol consumed during a drinking episode
- Hydration levels
- The amount of alcohol consumed generally
- Whether or not you have recently eaten
Factors that affect the rate at which you process alcohol that cannot be controlled include your age, metabolic rate, genetics, BMI and gender.
External factors include whether you take medications that could interact with alcohol, illicit drug use, hydration levels, if you have recently eaten, and the amount of alcohol your drink. all of these external factors can slow down the absorption of alcohol and the rate at which it is processed.
Women Process Alcohol Differently From Men
Alcohol affects women differently from men due to body composition and the way in which their bodies work.
Alcohol is primarily stored in the body’s water rather than fat. Generally, women possess a higher fat-to-water ratio than men, meaning they have less water to retain alcohol. As a result, alcohol consumed by women remains in their system for a longer period of time and at a more concentrated level.
Women also metabolise alcohol differently from men, resulting in slower elimination of alcohol toxins from their systems. The rate of stomach absorption in a female is significantly slower than in a man. This causes nearly all of the alcohol consumed to be absorbed directly into the bloodstream and leading to higher blood alcohol concentration.
Males and females also have variations in the amount and activity of alcohol dehydrogenase (ADH). ADH is the enzyme responsible for metabolizing alcohol.
Men have highly active forms of ADH in their stomachs and liver, whereas women have no ADH in their stomachs. This enables men to process alcohol up to 30 % faster than females.
Binge Drinking & Poor Liver Health Slow Down Your Body’s Ability To Process Alcohol
The health of your liver, whether you are male or female, and the amount of alcohol you consume within a drinking episode heavily impacts how long alcohol stays in your system.
Someone who has poor liver health and binge drinks will process alcohol a lot slower than someone who is in good health and drinks moderately.
A healthy liver processes, on average, one unit of ethanol per hour. However, this doesn’t apply to binge drinking. When a person consumes a large amount of alcohol over a short space of time, extra strain is placed on the organs, including the liver. Binge drinking results in a backlog of units that the liver has to process, and under strain, it will take longer than average.
Much like any organ in the human body, when it is overloaded, it works less efficiently. The liver causes alcohol toxins to remain in the body for longer, causing damage to organs and tissues.
Recognising The Signs of Alcoholism
Alcohol use disorders are progressive and on a spectrum, ranging from mild to severe. At the most severe end of the scale is alcoholism, where drinking alcohol takes over all aspects of a person’s life. This happens due to alcohol consumption causing lasting and pronounced changes in the brain’s pathways and reward system.
Recognising the signs of alcoholism in yourself or someone else is a vital factor in engaging help. After all, how do you know you need help if you do not know you have a problem in the first place?
Most people with alcoholism will know that they suffer. However, catching an alcohol use disorder in its early stages can help prevent a lot of harm and suffering.
Signs of Alcoholism:
- Tolerance: Needing to drink increasing amounts of alcohol over time in order to feel drunk
- Loss of control: Drinking at inappropriate times or frequently binging.
- Loss of choice: Losing the willpower to choose when you do and don’t drink alcohol
- Progression: Drinking more alcohol or swapping to stronger types of alcohol. You may or may not start to use medications and drugs with alcohol for greater effect.
- Craving: Experiencing an overwhelming need for alcohol
- Withdrawal: Experiencing alcohol withdrawals symptoms if your blood alcohol levels fall below a certain amount
- Continuation: Continuing to consume alcohol despite negative consequences to your mental and physical health, personal relationship, occupation or social life
- Relapse: Making genuine attempts to quit alcohol but not being able to
Someone with alcoholism will have a certain amount of alcohol in their system all the time. This doesn’t necessarily mean that they drink all day long, but when these levels fall below a certain amount, they will experience alcohol cravings and withdrawal symptoms.
Alcohol will stay longer in the body of a person with alcohol addiction than someone without the disorder.
Need Help To Reduce Or Stop Drinking?
If you frequently worry that you may test positive for an alcohol test, you may be considering reducing or stopping your alcohol intake. That being the case, Desistal is scientifically proven to help reduce unpleasant withdrawals from alcohol, making the process much easier and achievable.
Desistal contains two powerful nootropics that work to increase NAD+ (Nicotinamide Adenine Dinucleotide, the main metabolite required for cell function, which can be impacted by alcohol). This combination may help support brain function, promote balance, and reduce negative side effects associated with a post-alcohol withdrawal syndrome.
- Impaired driving : Get the facts: https://www.cdc.gov/transportationsafety/impaired_driving/impaired-drv_factsheet.html
- ‘Sobriety tags’ come into force: https://www.gov.uk/government/news/sobriety-tags-come-into-force
- Sensitivity of commercial ethyl glucuronide (ETG) testing in screening for alcohol abstinence: https://academic.oup.com/alcalc/article/42/4/317/160166
- Gender Differences in Alcohol Metabolism: https://sites.duke.edu/apep/module-1-gender-matters/content/content-gender-differences-in-alcohol-metabolism/
- Alcohol Metabolism. Clinics in Liver Disease. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3484320/