How Long Does Methadone Stay In Your System?

Written by Theresa Valenzky

& Medically Reviewed by Dr. Jessica Pyhtila, PharmD

Medically Reviewed

Last updated: 11/11/2022

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Last Updated - 11/11/2022

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Methadone is prescribed for pain and as part of a medication-assisted treatment program to help people dependent on heroin or prescription opioid painkillers. Although you may be instructed only to take the drug once daily, it can remain in your system for much longer. Knowing what to expect regarding how long methadone stays in your system is important if you take the drug.

How Long Does Methadone Last?

Methadone can last different time lengths, depending on why a person takes it. When prescribed for pain, a dose of methadone lasts four to eight hours. However, when prescribed for medication-assisted treatment (MAT) in opioid use disorder, methadone’s effects can last 24–48 hours.

Methadone Half-life 

A drug’s half-life is how long it takes the body to eliminate half of the dose. Methadone generally has a long half-life of 8–59 hours or even longer, which is highly variable depending on individual factors. It takes five half-lives for the body to eliminate a drug completely; therefore, methadone can remain in the system for a long time. Methadone metabolism differs with extended use, which can cause it to stay in the body even longer. Methadone is metabolized extensively, so testing for those metabolites in the body can also show whether someone has been taking methadone.

How Long Does Methadone Stay In Urine?

Both methadone and its metabolite EDDP (2-Ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine) remain in urine up to 14 days following the last dose.

How Long Does Methadone Stay In Hair?

Methadone can be detected in a 1.5-inch hair sample for up to 90 days after the last use.

How Long Does Methadone Stay In Blood?

Methadone and EDDP remain in the blood for up to 55 hours after the last dose.

How Long Does Methadone Stay In Saliva?

Methadone saliva tests are unreliable and, therefore, very uncommon. However, methadone can be detected in saliva for up to two days following the last use.

Does Methadone Show Up on a Drug Test?

It is common to find methadone on a drug test. Sometimes abbreviated mtd on a drug test, the specific tests for methadone can be conducted for several different reasons. This includes court, employer and doctor-ordered tests to ensure a person’s compliance with their prescribed methadone. 

False Positives for Methadone

Although extremely rare, methadone false positives can occur. A false positive is when a drug test confuses a different drug for methadone. Regarding methadone false positives, the most likely culprits are not even opioids and can include:

  • Verapamil, a blood pressure drug
  • Diphenhydramine, an antihistamine
  • Doxylamine, an antihistamine 
  • Quetiapine, an antipsychotic

If your drug test shows a positive for methadone, even though you do not take the drug, a confirmatory test should be conducted to rule out methadone.

Factors That Affect How Long Methadone Stays in Your System

Many factors determine how long any substance remains in the body. These include:

  • How often you take methadone: Methadone is a drug that accumulates, so the more often it is taken, the more it builds up and the longer it takes to be eliminated. 
  • Age: Younger and healthier people may eliminate drugs like methadone more quickly. 
  • Methadone dose: Higher methadone doses may linger in your body for longer than smaller doses. 
  • Medical history: Medical conditions like pregnancy can impact how long methadone stays in the body, with the drug lasting a shorter period in pregnant women during the second and third trimesters.
  • Drug interactions: Some drugs interact with methadone, causing methadone to last unexpectedly shorter or longer in the system.

Get Help for Methadone Addiction in Columbus, Oh

If you or someone you love struggles with methadone, the thought of quitting can be overwhelming. But you don’t have to struggle, and you are not alone. The Recovery Village Columbus is here every step of the way. Our medical detox program can wean you off methadone in a comfortable environment with round-the-clock care, and our inpatient and outpatient rehab programs can give you the tools you need to stay off methadone for good.

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