How long alcohol stays in your system and when it can be detected by drug tests
- Alcohol stays in your bloodstream and can make you feel drunk for up to six hours.
- But many factors, including weight, gender, and the pace of your drinking can affect this.
- A breathalyzer only detects very recent alcohol use, up to several hours before the test.
It can take up to six hours for alcohol to leave your bloodstream. That means you may feel soberer than you actually are, according to your blood alcohol content.
Medical term: Your blood alcohol content (BAC) refers to the percent of alcohol in your bloodstream - the higher your BAC, the drunker you will feel. In most states, a BAC of 0.08 is the legal intoxication level, meaning that it is illegal to drive with a 0.08 BAC or higher.
Moreover, how long alcohol stays in the system is different for everyone. Here are the different factors that matter and the various drug tests that can detect alcohol consumption months after you consume it.
How long does alcohol stay in your bloodstream?
According to Paula Zimbrean, MD, addiction medicine specialist and associate professor of psychiatry at Yale School of Medicine, factors that determine how long alcohol stays in the system include:
- Gender: A 2009 study found that when men and women drank the same amount of alcohol, women typically had a higher BAC than men. The researchers also found that women were more prone to negative effects associated with high BAC, such as blacking out, which they attributed to the differences in body mass, composition, and metabolism in women compared to men.
- Overall body weight: If two people of different weights drink the same amount of alcohol, the BAC will typically be higher in the person who weighs less, meaning that the alcohol will also stay in their system longer. This helps explain why women are generally more susceptible to alcohol than men.
- Rate of alcohol consumption: The CDC defines binge drinking as a man having five drinks within two hours or a woman having four drinks within two hours. Binge drinking causes your BAC to rise quickly because your body doesn't have as much time to metabolize all of that alcohol, which will cause you to become drunk more quickly.
How long does alcohol show up on a drug test?
Alcohol use can be detected on a drug test. Zimbrean says some federal agencies such as the Department of Transportation and Department of Defense may conduct drug and alcohol testing regularly. For non-federal employers, Zimbrean says drug test policies vary considerably, but you may be tested if you have a health care job or jobs involving driving, piloting, or air control.
Depending on the test, it may be able to identify alcohol use as far as months prior to the test. According to Zimbrean, here are the common drug tests and how far out they can detect alcohol use:
- Breathalyzer: Can only identify very recent use, within several hours.
- Alcohol serum and alcohol urine tests: Like breathalyzers, these can only be used to identify alcohol use within several hours.
- Alcohol metabolites test: These tests look for alcohol metabolites, which are small molecules leftover after your body metabolizes the alcohol. The tests can identify alcohol use around two to three weeks prior to the test, but if the hair is tested for metabolites, alcohol use from up to three months ago may be detected, says Zimbrean.
Risks of consuming alcohol
Consuming alcohol comes with many risks. Therefore, if you choose to drink, it's important to be aware of them.
Short-term risks
- Dangerous medication interactions: Zimbrean says that certain antibiotics mixed with alcohol can make someone immediately ill with symptoms such as nausea, vomiting, headache, or fainting. Additionally, other medications such as sleeping pills can be dangerous if taken shortly before or after drinking alcohol, since it may cause people to stop breathing. Even a few drinks mixed with sleeping pills can be lethal, Zimbrean says. Furthermore, some medications like benzodiazepines may cause symptoms such as lethargy or, in rare cases, seizures. If you're taking any medications, it's crucial that you check the warning labels.
- Injuries or accidents: Alcohol can cause difficulties with balance, dizziness, and lack of coordination, says Zimbrean. Because of this, alcohol can lead to dangerous and sometimes fatal injuries. According to a 2007 study conducted by the World Health Organization, alcohol causes 1.8 million deaths each year globally. The causes may range from falls to car crashes.
- Alcohol poisoning: If you drink excessive alcohol, especially in a short period of time (binge drinking) you risk getting alcohol poisoning, which can be fatal. Zimbrean says BAC of .25 comes with serious alcohol poisoning risks. How much you would need to drink to reach this BAC varies greatly depending on age, weight, and gender, but alcohol poisoning is something that will typically happen with heavy binge drinking.
Long-term risks
- Developing alcohol use disorder: Excessive drinking may lead to alcohol use disorder. Zimbrean says in these cases, alcohol causes significant problems with one's functioning, and it's associated with increased tolerance, meaning they need to drink increasing quantities in order to get the same effect. Risk factors for developing alcohol use disorder are family history of alcoholism, depression, PTSD, and recent psychological stress.
- Developing chronic health conditions: Long-term alcohol consumption increases your risk for certain chronic health problems, according to a 2011 study. These include:
- Cancer
- Diabetes
- Heart disease
- Liver disease
- Pancreas disease
- Impaired immune system: Chronic alcohol consumption disrupts the body's immune pathways, affecting the immune system in a way that makes it more difficult to fight off infections.
Insider's takeaway
If you drink alcohol, you should always consume with caution. Remember that alcohol stays in your system for a few hours, even if your mind feels clear. It's also important to consider the short-term and long-term risks of drinking alcohol, and weigh the pros and cons before you drink.
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