One common concern of people who use illicit drugs like meth is how long it stays in the system.
Meth will generally remain detectable for up to four days. The exact timeframe can depend on the type of drug test used and other personal factors.
Methamphetamine (meth), also known as crank or crystal meth, is a highly addictive drug that is chemically similar to the drug amphetamine.
Methamphetamine is a schedule II drug that has a high potential for abuse and addiction and is illegal for recreational use.
A prescription form of methamphetamine (Desoxyn) is sometimes prescribed to treat ADHD and obesity.
Meth Detection Times
The detection time of a drug refers to how long it can be detected in a person’s body.
Substance use can be detected through a variety of drug tests—all of which can vary in their sensitivity and accuracy.
Drug tests and detection times for meth:
- urine tests: one to seven days
- blood tests: one to three days
- saliva tests: up to two days
- hair tests: up to 90 days (three months)
How Long Meth Remains In Urine
Urine screenings are the most common type of drug test. A single use of meth can be detected in the urine for one to four days on average.
Taking a lot of meth may cause it to remain in the urine for up to a week, or seven days.
Learn more about detecting meth in urine
How Long Meth Remains In The Blood
Meth can also be detected in a blood sample. Blood tests may detect meth use for one to three days on average.
Learn more about detecting meth in blood
How Long Meth Remains In Saliva
Oral fluids, like saliva, may be tested for drug use. People who get a saliva test may test positive for methamphetamine use for anywhere from a few minutes to 48 hours after taking meth.
How Long Meth Remains In Hair
Hair testing can detect drugs for the longest amount of time. These tests involve analyzing samples of hair follicles from the head, armpit, or other areas of the body.
Hair tests can detect the use of drugs, including meth, for up to three months.
Learn more about detecting meth through hair tests
Factors That Can Influence Meth Detection Times
The timeframe for how long someone will test positive for meth may depend on a wide range of biological and personal factors.
These factors can include:
- Frequency of use: If you use meth regularly, this can cause a buildup of the drug in your system, affecting detection times.
- Amount of meth used: Taking larger amounts of meth can cause it to stay in your system longer.
- Method of use: The amount of time meth stays in your system can depend on whether you’ve snorted, injected, smoked, or taken the drug orally.
- Body composition: Personal factors such as weight, body fat, and metabolism can affect drug detection times.
- Polydrug use: Using multiple drugs (including alcohol) can affect how long drugs stay in your system.
Why Are People Tested For Meth Use?
Drug tests can be ordered by a judge, employer, or healthcare provider.
Common reasons why drug tests are ordered:
- pre-employment
- workplace drug testing
- court-mandated drug testing
- forensic purposes
- suspicion of drug use
Your doctor may order a drug test if you are showing signs of illicit meth use. Most drug tests are conducted in a medical or laboratory setting.
Can You Get A False Positive For Meth?
The accuracy of drug tests can vary. The use of some over-the-counter (OTC) medications and prescription drugs may cause a false positive for illicit drug use.
Tell your doctor or lab technician if you are taking any drugs, as this may affect testing results.
Finding Treatment For Meth Use And Addiction
It’s common for people who are using drugs to search for how long their drug use can be detected through a drug screening.
If you or a loved one is using meth: You’re not alone. But it may be time to talk to a doctor about getting help. Inpatient treatment or outpatient treatment may be recommended.
For more information about methamphetamine addiction treatment options, call our helpline today.
Addiction Resource aims to provide only the most current, accurate information in regards to addiction and addiction treatment, which means we only reference the most credible sources available.
These include peer-reviewed journals, government entities and academic institutions, and leaders in addiction healthcare and advocacy. Learn more about how we safeguard our content by viewing our editorial policy.
- Redwood Toxicology Laboratory—Laboratory Testing Reference Guide
https://supremecourt.nebraska.gov/sites/default/files/Programs/CIP/events/redwood/LAB_Reference_Guide.pdf - U.S. National Institute on Drug Abuse (NIDA)—Methamphetamine DrugFacts
https://www.drugabuse.gov/publications/drugfacts/methamphetamine - U.S. National Library of Medicine: MedlinePlus—Drug Testing
https://medlineplus.gov/lab-tests/drug-testing/