How Long Does Meth Stay in Your System?

Methamphetamine stays in your system for approximately:

The amount of time that meth stays in your system depends on the dose ingested, frequency of use, and your body’s ability to process it.

What is Meth?

Methamphetamine is the second most popular illicit drug in the world, after marijuana. It is commonly sold under the street names meth, crank, crystal, crystal meth, glass, ice, and speed. 

In the United States, it is considered a schedule II drug, meaning it has a high potential for misuse and a high risk for developing a severe mental or physical dependence (addiction).

It does have limited medical usage and can be prescribed under the brand name Desoxyn to treat ADHD or obesity. However, it is rarely prescribed as safer drugs such as Adderall and Ritalin are now available.

Effects of Meth

Methamphetamine increases the brain’s production of dopamine, a chemical that is involved in body movement, motivation, and rewarding behaviors.

Adverse short-term side effects of meth use include:

• Agitation
• Inability to focus
• Poor balance and coordination
• Inability to follow directions
• Inattention
• Depressed reflexes
• Increased reaction time
• Motor excitation
• Restlessness
• Time distortion

Adverse long-term side effects of meth abuse include:

• Malnourishment
• Extreme weight loss
• Severe dental problems ("meth mouth")
• Itching, leading to skin sores from scratching
• Anxiety
• Changes in brain function
• Memory loss
• Sleeping problems
• Violent behavior
• Paranoia
• Hallucinations

Mental Health Risks

Psychosis has been reported as an effect of long term use. Psychosis is a severe mental disorder that impairs your thoughts and emotions so much that you lose contact with external reality. Meth-induced psychosis can occur during intoxication or afterward during withdrawal.

Meth Addiction

Crystal meth is one of the most addictive drugs in the world. Because it has such a powerful effect on the brain’s reward system, even first-time meth users have a very strong drive to use it again. After just a few uses, people can develop psychological or physical dependence, especially if the drug is smoked or injected.

Meth Withdrawal

Because the physical addiction to meth is very intense, withdrawal symptoms are also severe. Withdrawal symptoms can begin approximately 24 hours after the last dose. Generally, the heavier the drug use, the worse your symptoms will be.

Meth withdrawal symptoms include:

• Constipation
• Diarrhea
• Shaking
• Itchy eyes
• Joint pain
• Headaches
• Clammy skin
• Hyperventilation
• Irregular heartbeat
• Psychosis
• Depression

How Long Does Meth Last?

Users can inject, smoke, swallow, or snort methamphetamine. Injecting or smoking will cause the drug to reach the brain very quickly, causing a “rush” or “flash” of euphoria. The high will be more intense but wear off quicker. Swallowing or snorting the drug will cause the high to be spread out up to 12 hours, and aftereffects can last up to 24 hours.

Half-Life of Meth

The half-life of methamphetamine is approximately 10 hours. This means that after 10 hours, half of the ingested dose has been metabolized and removed from the bloodstream.

Drug Testing for Meth

After ingestion, meth enters your urine, sweat, blood, and hair. All hair and fluid samples can be tested for meth. However, urine testing is the most common and cost-effective type of drug test.

How Long Does Meth Stay in Your Urine?

Meth will show up in your urine within an hour of ingesting the drug. A urine test can detect meth one to three days after the last use for occasional users, and seven to ten days for very heavy users

How Long Does Meth Stay in Your Blood?

Meth typically leaves your bloodstream completely after 48 hours. However, a blood test may be able to detect it after three to four days in chronic users who ingest large doses.

How Long Does Meth Stay in Your Saliva?

Meth remains in your saliva for one to four days after the last use. A cotton swab can collect oral fluid from your mouth for a saliva test.

How Long Does Meth Stay in Your Hair?

Meth reaches your hair follicles seven to ten days after use and remains in them for up to 90 days. However, hair tests are typically more expensive than other methods of testing. Further, their results are more controversial as environmental contamination may cause false positives.

Meth Addiction Treatment Options

Meth addiction is treated similarly to most substance use disorders. While there is no FDA-approved medication to treat methamphetamine use, there is a wide range of treatment programs that help individuals recover through detox, behavioral therapy, and peer support.

A comprehensive program at an inpatient treatment facility provides the best hope for meth recovery.