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Methocarbamol was the 178th most commonly prescribed drug in the United States in 2017. In that year alone, there were over three million prescriptions. Considering how popular this drug is right now, it pays to know a little bit more about this medication, including how long methocarbamol stays in your system.

 The FDA states the following information regarding methocarbamol half-life:

Mean effective half-life: 1 to 2 hours

Time to steady-state: N/A

Mean accumulation ratio: N/A

Terminal phase half-life: 1 to 2 hours

Methocarbamol is absorbed by the body, binding with plasma proteins at a rate of 46 and 50 percent. Once metabolized, excretion is through urine. 


What is the half-life of methocarbamol?

Between 1 to 2 hours.

How long does methocarbamol stay in your system?

Methocarbamol is detectable in your system for the following time frames:

This means that after the last dose, methocarbamol is detectable in saliva, urine, and hair tests for the named time. 

Will methocarbamol cause you to fail a drug test?

It is possible it may cause someone to fail a drug test. It doesn’t fall into a category for commonly abused drugs, though. 

Does methocarbamol need to build up in your system?

The liver breaks down methocarbamol. It may build up for those with liver disease, increasing the side effects for future doses of the drug. Studies show that people with cirrhosis secondary to alcohol abuse had a 70 percent reduction in the clearance of this drug, thus leading to more adverse effects.  

Disclaimer: this article does not constitute or replace medical advice. If you have an emergency or a serious medical question, please contact a medical professional or call 911 immediately. To see our full medical disclaimer, visit our Terms of Use page.

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