How Long Does Methamphetamine Stay in Your System?

Dr. Langdon M.D.

Medically Reviewed By: Kimberly Langdon M.D.


Methamphetamine has devastated entire regions of the country. Although the opioid crisis has taken more attention in the media lately, meth use is still widespread. Meth is a fast-acting drug, but it stays in your body longer than you might think.

How long meth will stay in your system depends on a few things, including:

  • Whether you have been using other drugs
  • How mentally and physically healthy you are
  • Your history with meth abuse

If you’re wondering about how long it will be detectable by a drug screening, then you also need to consider what kind of drug test you are taking.

How Long Does Methamphetamine Stay in the Body?

Once taken, meth hits fast. Within seconds of injecting or smoking it, users often feel an initial ‘rush’ as dopamine floods their brain. Next, the ‘high’ of meth can last for 4-14 hours

Short-term effects of meth may include:

  • Increased attention
  • Increased activity
  • Euphoria
  • Decreased appetite
  • A faster rate of breathing
  • Fast heartbeat

However, once these body and brain effects wear off, that does not mean that meth is out of your system. In fact, the period when users are ‘high’ is just the beginning of meth’s time in their system.

How Long Does Methamphetamine Stay in Your Urine?

Methamphetamine can stay in your urine for up to four days. This means that if you take a lab test for drugs and it uses a urine sample, you will need to have been sober for at least 4 full days to ensure that you test negative for meth.

Urine tests are, by far, the most common type of tests found in workplaces. They are cheap, effective, and they have a fairly long detection window. Plus, they do not require invasive methods to get a testing sample. 

How Long Does Methamphetamine Stay in Your Hair?

Hair testing makes it nearly impossible for users of meth to try and plan their use around drug tests, or to detox meth quickly after use to avoid a positive test result. Hair testing has been known to find traces of meth for up to six months after the last time taken.

The downsides of hair sampling are that it is more invasive than urine testing (requires a hair to be plucked from the body or head), and it is more expensive. Plus, hair testing is known to be less accurate than other forms of testing. 

Still, there is no way to ensure that a test will not be taken via hair – and if you have used meth any time in the past 6 months, you could test positive!

How Long Does Methamphetamine Stay in Your Blood?

Meth has an average half-life of around 11 hours in the blood. This means that it takes about 11 hours for half the meth to leave your bloodstream. But a drug’s time in the blood is not simply two half-lives.

In fact, a blood test can detect meth for one to four days after the last dosage. Blood tests require a blood sample, so they are more invasive than other tests. They are fairly expensive and have a shorter detection window than urine tests.

The benefit of blood testing is that it is highly accurate. Very few false positives or negatives are produced via blood testing. For this reason, these tests are most common in legal settings, as well as law enforcement contexts.

How Long Does Methamphetamine Stay in Your Saliva?

In order to conduct a saliva test, a simple cotton swab from the inside of the cheek is all that is needed. 

This testing method is known to find traces of meth for one to four days after the last use. It is important to remember that this is not the same for everyone, and the test might detect the drug for a shorter or longer period of time, depending on other factors.

Saliva testing is easy to do and is non-invasive, like urine testing. Because this test can be administered in public, it is commonly used by police officers in the field. However, these tests are more expensive and less accurate than urine tests so, they are less common in the workplace.

Factors That Affect How Long Methamphetamine Will Stay in Your System

The method of drug testing for meth is important to consider in some cases, but how long it lasts in your system is affected by many more factors. These factors should always be taken into account when trying to determine how long meth will stay in your body:

Physical Factors

You can’t speed up the process of detoxing from meth. Your body takes time to process the drug.

That said, the amount of time this will take may depend on several things, including:

  • Age
  • Genetics
  • Metabolism
  • Weight
  • Gender
  • Health

Many systems in your body must coordinate in order to process meth. In particular, the liver and kidneys play a key role. Without proper function of these organs, meth will get backed up in the system and take longer to leave.

Mental Factors

Physical well-being is not the only thing that can affect meth’s time in the body. Mental illnesses that are commonly present in meth users, such as anxiety and depression, can slow down processing times as well.

Methamphetamine Use Specifics

Perhaps the most important variable is how the meth was used. With heavy, prolonged use, meth builds up in the body and can take longer to remove.

These factors can affect this timeframe:

  • Frequency of use
  • Duration of use
  • How it was taken (smoked, injected)
  • Presence of other drug or alcohol abuse
  • Dosage

In general, the heavier the meth abuse, the longer it will take to detox. Furthermore, a person who has been using heavily is unlikely to be in good mental or physical health, which will only prolong the process even more. 

Treatment for Methamphetamine Addiction

Meth abuse is never to be taken lightly. If you or anyone you know has been using this dangerous substance, call Bedrock Recovery Center today to get treatment for meth addiction.


Written by Bedrock Recovery Center Editorial Team

© 2024 Bedrock Recovery Center | All Rights Reserved

* This page does not provide medical advice.

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