How long does meth stay in your system?

Methamphetamine has a longer half-life than many other stimulants, meaning it stays in your system longer than cocaine or Adderall. Detection windows vary significantly based on the test type and usage pattern.

Detection by test type

Urine testing detects methamphetamine for 3-5 days after single use and up to 7-10 days after heavy or chronic use. Meth is metabolized into amphetamine, and both are detected on urine screens. Blood testing detects meth for 1-3 days. Saliva testing detects meth for 1-4 days. Hair follicle testing can detect methamphetamine use for up to 90 days.

Why meth stays longer than other stimulants

Methamphetamine has a half-life of approximately 10-12 hours — meaning half the drug is still in your system 10-12 hours after use. Compare this to cocaine's 1-hour half-life. This longer half-life is why meth produces effects lasting 8-12 hours (compared to cocaine's 30-60 minutes) and why it remains detectable longer. Crystal meth and smoked meth may have slightly different absorption rates but similar elimination times once in the bloodstream.

Factors affecting clearance

Urine pH plays a significant role — acidic urine accelerates meth excretion, while alkaline urine slows it. This is why some sources recommend acidic foods or drinks, though the effect is modest and not a reliable strategy for passing a test. Dosage and frequency of use are the primary factors. Route of administration (smoking, injecting, snorting, oral) affects onset but not elimination half-life. Overall health, kidney function, age, and hydration all play secondary roles.

Treatment for meth addiction

If meth use has become a pattern, treatment is available and effective. Unlike opioid addiction, there are no FDA-approved medications specifically for methamphetamine use disorder, but behavioral therapies — particularly contingency management and CBT — produce strong results. Read our substance abuse treatment guide or search our directory.

Find a location near you

Authoritative sources

This article references guidelines from: NIDA · SAMHSA · CDC · FDA · ASAM

Frequently asked questions

Disclaimer: Informational only. Not medical advice. SAMHSA: 1-800-662-4357.