Understanding drug detection times may help you anticipate the chance of a positive drug test result.

As such, these illicit drugs are detectable in your system through urine, saliva, blood, and hair tests.

Drug Test

However, the results depend on different factors: type of drug, dosage and frequency of use, metabolism, and drug test type.

Typically, all drugs have unpredictable periods of effect. A crystal meth high hits for 6–12 hours, whereas cocaine’s euphoric effects peak within two hours.

Read on to learn about drug detection times while understanding the factors that may influence the likelihood of a positive result.

Factors Affecting Drug Detection Times

One can assume that once the drug’s effects settle down, a drug test won’t identify its presence. Note that the body takes a while to break down metabolites and clear them out of your system. Even if you’re sober, you may still fail the toxicity testing.

Here’s an overview of the significant factors that affect how long drugs stay in your system.

  • Type of drug used
  • Metabolism and individual factors
  • Dosage and frequency of use
  • Type of drug test

Furthermore, your gender may also influence the drug detection times since men and women metabolize drugs uniquely. In particular, the metabolic differences lie in weight, body fat percentage, age, cellular hydration levels, and hormones.

Common Types of Drug Tests

Usually, commonly abused substances are detected through the following drug test types.

  • Urine Testing
  • Blood Testing
  • Saliva Testing
  • Hair Testing

Generally, several substances stay in urine longer than they do in blood or saliva. Specifically, metabolites can be detected for up to 3–4 days in urine and only last minutes to six hours in blood and saliva.

On the other hand, hair testing is the most expensive. It’s also the most accurate and difficult to tamper with. Through this test, metabolites are detectable for 90 days max. Hence, it has the longest drug detection time of all tests.

Drug Detection Times for Commonly Abused Substances

The type of drug is a significant factor that determines the duration these substances take to leave one’s body.

Certain drugs offer a short buzz and instant burnout, whereas some take longer to take effect yet stay in the body for a while.

Below are the drug detection times of commonly abused substances.

1. Alcohol

Standard drug test excludes alcohol. However, there are rapid tests to verify alcohol detection time if necessary.

  • Between 12–48 hours in urine
  • Three months for hair testing
  • Up to three days in saliva

2. Amphetamine

The detection time for amphetamines differs from one drug to another. For instance, amphetamine can stay in your blood for 4–6 hours while its metabolites are still detectable in urine for at least three days.

In most cases, a positive drug test result suggests an individual has taken amphetamines constantly in the past 3–4 days.

Nevertheless, in frequent drug users, the detection time may last at least one week following the last consumption.

3. Barbiturates

Barbiturates’ detection times in urine, blood, saliva, and hair mainly depend on the drug taken.

For example, 50mg of butalbital can be detected in blood and saliva within 15–60 minutes after administration, while 30mg of Phenobarbital is detectable in all test forms through 48–52 hours.

In some scenarios, barbiturates can be detected in urine for up to six days and a max of three months for hair samples.

4. Cannabis

Cannabis tests primarily detect a substance known as tetrahydrocannabinol (THC), which causes users to get high.

Compared to someone who puffs cannabis multiple times a week, first-time smokers are highly likely to survive a drug test.

Although, detection times differ depending on the following tests:

  • Up to 30 days in urine testing
  • 90 days in hair testing
  • Four hours in blood testing
  • 72 hours for saliva

5. Cocaine

Cocaine is a stimulant that can influence your emotions, breathing, and heart rate. Its effects vary depending on the manner of intake<.

In particular, snorting cocaine will hit within 3–5 minutes, while injecting or smoking can take effect in seconds.

The detection times for cocaine may last between 2–14 days in blood, saliva, and urine based on the frequency of use and 90 days in hair.

6. Methamphetamine

Crystal meth is an intoxicant with sudden effects. Meth’s first blow takes around 30 minutes and the buzz effect stays for a couple of hours.

Some meth is excreted by the body before metabolizing it. However, tests may still identify metabolites as it dissolves the leftover substance.

Hence, meth can be detected in your body for 1–25 days in urine, saliva, and blood. While it lasts up to 90 days for hair.

7. K2 or Spice

Based on a study, this drug may cause users to develop suicidal thoughts, violent behaviors, and erratic heart rates.

The detection times of spice are significantly affected by how often the user smokes it.

In general, K2 can be detected in your system for up to 72 hours if urine, saliva, and blood are tested. For hair, it can last for 90 days.

How to Interpret Drug Test Results?

A negative result indicates that substances weren’t found in the sample.

Often, test results show negative results despite the presence of substance traces.

As a general rule, specified cut-off levels of drugs should be identified before the result is considered positive. Whereas, if the test finds lower cut-off levels, the result will show as negative.

Understanding False Positives and False Negatives

False positive results mean a specimen is marked as positive when it’s really substance-free. Conversely, a false negative may happen when a sample is clear even though the patient took drugs before the test.

A false positive result might happen due to the following factors:

  • Wrong testing procedures
  • The drug test threshold value is very low
  • Other compounds similar to drug metabolites are detected

On the other hand, a false negative can happen if:

  • A test sample is tampered with, for example, in urine
  • The cut-off level is too high

The preliminary drug test should be verified by confirmatory testing methods whether the result is a false positive or false negative. Doing this will decrease the chance of getting inaccurate test results.

Confirmatory Testing Methods

A confirmation test is used as the definitive testing method to verify a positive result.

Commonly, a screening result indicates that a type of drug is positive, not necessarily which specific compound triggered the positive result.

In this case, the specimen will need to undergo a few confirmatory testing methods.

1. Gas Chromatography-Mass Spectrometry (GC-MS)

The GC-MS test in urine analyzes and presents a precise report of the specimen’s chemical composition. Thus, it’s regarded as the “gold standard”.

Additionally, this test can detect the existence of any minute metabolites in a sample.

Despite its remarkable accuracy, it’s not the primary option for alcohol and drug testing because it’s complicated and expensive.

2. Liquid Chromatography-Mass Spectrometry (LC-MS)

LC-MS is commonly used with immunoassays to present high-quality drug test results in urine and blood.

This confirmatory test is sensitive and specific, which detects low quantities of illicit substances.

Considering the precision and dependability of LC-MC, it’s frequently utilized in court orders and forensic investigations.


Overall, unless you stop using drugs, there’s nothing you can do to speed up drug detection times.

However, by understanding drug detection times, you could make sound drug-related decisions and stay ready for future tests that you may be required to take.

Indeed, it’s tough to conquer drug dependence. So, if you or someone you know is battling drug abuse, we at Recreate Life Counseling can help.

We offer personalized, all-inclusive therapies to get you on your way to sobriety. Our compassionate and devoted team members are ready to rebuild people’s lives one step at a time.


  • Why is it important to know how long drugs stay in your system?
  • What factors influence how long drugs stay in your system?
  • How long does marijuana stay in your system?
  • How long do opiates stay in your system?
  • How long does alcohol stay in your system?
  • How long does cocaine stay in your system?
  • How long do benzodiazepines stay in your system?
  • How long do amphetamines stay in your system?
  • How long does MDMA (Ecstasy) stay in your system?
  • Can you speed up the elimination of drugs from your system?

Please note that these detection times are approximate and can vary depending

Related Articles

Published on: 2023-02-28
Updated on: 2024-05-10