How Long Do Drugs Stay in Your System

There are various reasons why you might ask the question: how long do different drugs stay in my blood, urine or hair? 

But before we get into the science of how long do drugs stay in your system, it’s important to acknowledge that the answer will be specific to the drug that is being tested for by employers or law enforcement agencies.

We’ve covered the specifics of pre-employment drug testing in another article. Here, let’s focus on substance abuse problems and how long different drugs can stay in your body.

In this study, we’ll go through commonly abused illicit drugs and estimate the detection time for each of them, depending on factors like gender, testing method and drug tolerance.

Let’s begin with a term that is often referred to when discussing substances’ metabolism and potency — namely, drug elimination half-life, which is important to determine how long metabolites can be detected in urine samples or by other ways of drug screening.

What is a drug’s half-life?

In a nutshell, the half-life of a drug is simply the time it takes for given quantity — or its concentration in a person’s blood plasma — to be halved1

This fact is important because it is then possible to determine how long it will take for a substance to stop having any effects on the user and the amount of time after which drug use won’t show up on drug test results.

Factors that can impact drug half-lives

The metabolism of prescription drugs or illicit substances differs from one person to the next. 

  • Person’s age must be considered when estimating how long drugs continue to offer therapeutic properties for a drug user. The older you are, the longer it will take for your body to metabolize drugs.
  • Body weight can also alter how your body processes certain substances. The amount of physical activity you do can impact the metabolization capabilities of your body. Even the types of foods that you eat can cause your body to metabolize drugs differently. 
  • Cranberry juice is known to inhibit the ability of your body to metabolize certain drugs, leading to an increased amount of the drug being in your blood. This can lead to the drugs being detectable in your system for a longer amount of time.
  • Health conditions can impact a drug’s half-life in your body, with people suffering from long-term illness being less able to metabolize most drugs as quickly as a healthy person.

Short acting drugs can come on quickly to someone with no medical complaints. If you have kidney or liver issues and consume drugs processed by these organs, then metabolization will be much slower.

Drug detection times

There are many variables that can alter the ability your body has to break down a drug into metabolites, and therefore, how long drugs can be detected in your body

The unpredictable nature of how drug use interacts with each person’s own body chemistry makes it difficult for experts to calculate specific elimination half-lives for every single person.

Trying to decipher how long drug use can be detected in someone’s body is hugely dependent on a number of individual factors including body mass and condition of central nervous system. All bodies are different.

However, scientists can assert what the maximum detection time is for majority of drugs. And this length of time will differ depending on factors such as type of drug test that is being performed. 

The most common drug tests are done by requesting either blood test, urine test, or hair test — substances can be detected in your body using all of these methods.

We’re now going to look at drug detection timelines within your system when doing these three types of drug tests for most commonly abused substances in the U.S.

How long does alcohol stay in your system?

Alcohol is one of the most commonly used drugs in the country, with the latest figures suggesting that 86.3% of Americans over 18 years old will have drank some form of alcohol during their lifetime2.

Most people don’t think of drinking alcohol as drug use, but the effects can be detrimental as any other drug has been abused. Alcohol can also have a damaging effect on many parts of the body, like brain and especially the liver.

Drinking alcohol is using drugs, as odd as it sounds. If you stop drinking, and experience withdrawal symptoms, you may be a victim of alcohol abuse.

Here are some facts about alcohol and its byproducts:

  • The number goes down to 70% when it comes to alcohol being drunk within the last year. 
  • Approximately 55% of Americans said they had drunk alcohol in the last month when the study was done in 20183
  • Alcohol use can have a long term effect on the body, with many Americans dying each year.
  • On average, a typical American will drink around 2.3 gallons of alcohol per year.  

When it comes to maximum drug detection times, these are important numbers for alcohol metabolites:

Way of testingAlcohol detectable
Blood drug testOne day
Urine drug testTwo days
Mouth swab drug testUp to 3 days
Hair drug testUp to 90 days

How long does amphetamine stay in your system?

Amphetamines come in a various forms and have varying effects on the body. This drug is available in prescription form – often helping people with ADHD (attention deficit hyperactivity disorder). In certain situation, amphetamines can be prescribed as part of treatment process for other diseases.  

Below are amphetamine (Adderall) and methamphetamine detection times:

Adderall46 hours50 hours72 hours
Meth72 hours4 days1 week

Both drug traces can be detected in hair follicles for up to 90 days after last use.

How long do barbiturates stay in your system?

Barbiturates are known for their soothing qualities. That’s why they’re often prescribed as sedatives for treating sufferers of anxiety. In some situations, barbiturates are offered to patients who struggle with insomnia, as they’re known for inducing sleep. They can also provide relief to people with epilepsy, as they can help prevent both seizures and muscular spasms.

Type of screenBarbiturates detectable
Blood testUp to 72 hours
Saliva testUp to 72 hours
Urine test1 to 3 weeks
Hair testUp to 90 days
Detectable concentration of barbiturates

How long do benzodiazepines stay in urine?

Benzodiazepines – often referred to as ‘benzos’ – is a category of drug that is known for its sedative properties. Benzodiazepines incorporate a wide range of prescribed drugs, including Xanax, Valium, Halcion, Ambien, and Klonopin. Similar to barbiturates, they can be prescribed for people who suffer from issues like anxiety and epilepsy.

Each type of benzodiazepine has a slightly different detection window. Let’s have a look at each of them separately:

Xanax24 hours2.5 days4 days*
Valium48 hours10 days6 weeks
Ativan (Lorazepam)72 hours8 hours6 days

*Xanax can be detected in urine sample for up 7 days for regular users. It also largely depends on the individual person’s body mass, their recovery rate, etc.

Above benzos can be detected by hair test for up to 90 days, except for Lorazepam, which is detectable for up to 30 days after last use.

Does urine drug test detect hallucinogens?

Hallucinogens are a catch-all term for a variety of substances that range from synthetic, like MDMA and natural, classic drugs like Magic Mushrooms – or Psilocybin, to give it its chemical name.

These drugs are often used recreationally. But, more recently, they have been used to aid the therapeutic treatment of people who have PTSD, as well as other trauma-related mental health issues.

Let’s look at some of the most commonly consumed hallucinogens and how long they remain detectable in your system via the main drug testing methods:

Ketamine4 days11 days
LSD (Acid)12 hours4 days
Mescaline1 day10 days3 days
PCP (Angel Dust)1 day10 days4 weeks
Psilocybin (Shrooms)1 day1 day
MDMA (Ecstasy)48 hours2 days4 days

Traces of these hallucinogens can be detected by hair test for up to 90 days after last use.

How long does marijuana stay in your system?

Marijuana is known by several other names, and it is legal in some states. Marijuana is used for recreational purposes, and it can also be used to aid medical conditions such as cancer treatment or glaucoma. The psychoactive chemical in marijuana is THC, which is not present in hemp CBD products.

Ways of testingTHC (Marijuana) detectable
Blood testsUp to 4 hours
Saliva testsUp to 72 hours
Urine testsUp to 30 days
Hair testsUp to 90 days
Timeline of detectable marijuana use

How long do opioids stay in your system?

Opioids include street drugs like heroin, as well as synthetic drugs that are prescribed for treatment such as pain relief. 

Morphine72 hours72 hours72 hours
Codeine24 hours4 hours72 hours
Fentanyl48 hours72 hours
Heroin6 hours1 hour72 hours
Hydrocodone24 hours36 hours96 hours
Oxycodone24 hours96 hours96 hours
Tramadol48 hours48 hours72 hours
Longest detectable time of opioid use by type of drug test

Byproducts of the above opioids can be detected by hair follicle drug test for up to 90 days after last use.

How long does cocaine stay in your system?

Stimulants can include illegal substances such as cocaine, as well as the amphetamines that we’ve already covered. The chemical metabolite that will show for cocaine use is benzoylecgonine.

Here’s a chart that shows how many days cocaine traces can be detected:

Type of testCocaine detectable
Blood drug screensUp to 24 hours
Mouth swab drug screensUp to 48 hours
Urine drug screensUp to 72 hours
Hair drug screensUp to 90 days

Types of drug testing

The following are the four main types of drug testing. Each type of drug test is better suited to different substances. Here is a quick outline of the methods:

Urine testing

Urine drug test is quite possibly the best way to detect substances as it is reliable, allows for a large sample size, and can be processed cheaply. But this drug test does have drawbacks too. In some cases, a person may not be able to pass urine testing.

Saliva testing

Mouth swab drug tests are only used when it is suspected that drugs have been consumed within a relatively recent time frame. A swab is simply run over the inside of a person’s mouth. 

Blood testing

Blood tests require plasma to be extracted, making them more invasive than other main testing methods. Like mouth swab test, it is only worthwhile when checking for recently consumed drugs.

Hair testing

As you will have noticed from our list, drugs are often detectable for much longer periods in hair follicles. And that’s why this is a common test used for drugs. However, Hair Follicle drug tests can offer inconclusive results, especially if a recreational or low-usage drug user is tested.


The amount of time how long do drugs stay in your system will vary depending on specific drug metabolites and method of testing used.

The time it takes to eliminate drugs from your system also depends on factors such as hydration (amount of drinking water), drug use frequency, metabolic rate, and even acid-base balance in urine.

Suppose you or a loved one are struggling with withdrawal symptoms or other side effects of substance abuse. In that case, organizations like Alcoholics Anonymous and Narcotics Anonymous can help get in touch with addiction treatment expert to work on a drug detox program or other treatment options.

Data sources: National Institutes of Health, American Addiction Centers, National Institute on Drug Abuse, Footprints to Recovery.