How Long Does Flexeril Stay in Your System?

  • Written by:

    Bedrock Recovery Center

  • Dr. Manish Mishra, MBBS
    Medically reviewed by:

    Dr. Manish Mishra, MBBS

How Long Does Flexeril Stay in Your System?

Flexeril is a brand name for cyclobenzaprine. This muscle relaxant is not included on standard 5-panel and 10-panel drug tests. But special tests geared towards finding only cyclobenzaprine can be used. These tests may be necessary for prescription monitoring or in the aftermath of an accident or overdose.

When taking Flexeril, brain effects occur within an hour of consumption. Effects wear off after about 12-24 hours. But it’s important to remember that the substance remains in your system even after effects wear off. 

If you’re new to using this drug, you may be wondering how long Flexeril stays in your system. Here’s what you need to know.

How Long Does Flexeril Stay in Lab Tests?

This depends on the type of test done. A hair test can show a substance that was consumed as long as three months ago. Blood, saliva and urine tests have ticking clocks attached to them. They’re only practical for very recent drug use.

But it also depends on the drug itself. Cyclobenzaprine has an average elimination half-life of 18 hours. The half-life for the drug can be as low as eight hours and as high as 37 hours. This range includes extended release versions of the drug. 

In general, it takes about five half-lives for a substance to exit the body. This means that Flexeril could show up in lab tests around four days after the last time taken, or up to about eight days later. 

How Long Does Flexeril Stay in Your Urine?

Urine testing is the most common method of drug testing.

Norcyclobenzaprine is Flexeril’s primary metabolite which is detectable in urine. Urine screenings can usually find evidence of the drug between three and eight days after the last use.

How Long Does Flexeril Stay in Your Hair?

As mentioned above, hair tests generally show patterns of drug use over the 90-day period before the test. Evidence of a drug can be visible about a week after ingestion when there is new hair growth. But hair testing for Flexeril use is rare.

How Long Does Flexeril Stay in Your Blood?

Flexeril reaches peak levels in the blood about seven to eight hours after consumption. So, a test done then would produce a positive result. With a long half-life, the drug is detectable in blood for around three days. This window of detection can be longer.

How Long Does Flexeril Stay in Your Saliva?

Oral fluid tests tend to be more expensive than other types of biological samples. Saliva testing for Flexeril is uncommon. There is little information available about how long the drug is detectable in saliva. But some sources suggest the drug can be found up to around 36 hours after consumption

To summarize, Flexeril is typically detectable within these periods of time:

  • blood  – up to 3 days
  • saliva – up to 36 hours
  • urine – up to 8 days
  • hair – up to 90 days

If you have to do a drug test and you have a prescription for cyclobenzaprine, make this fact known. This information will inform how your test results are interpreted. 

Also, be aware that Flexeril is very similar in structure to tricyclic antidepressants (TCAs). Using Flexeril can trigger a false positive for a TCA.

Can You Detox From Flexeril Faster?

Every person is unique. So the rate at which the body processes Flexeril is not the same for everyone. How long it lasts in the body depends on various factors.

These include but are not limited to:

  • Frequency of use
  • Duration of use
  • Dosage
  • Presence of other substances
  • Metabolism
  • General health
  • Age
  • Weight
  • Genetics

Let’s take a look at some of these factors. 

Elderly people over the age of 65 tend to take longer to process substances than younger adults do. In fact, Flexeril may not be suitable for older individuals.

Flexeril can accumulate in the body with regular use. Someone who has been taking the medication for a while will need more time to rid themselves of the substance. 

The kidneys and liver are essential detox organs. Thus, impaired kidneys or liver disease can extend the process of detoxing.

Those with a higher body mass index are able to metabolize substances faster than their smaller counterparts. 

A healthy lifestyle can result in a faster metabolism. So, for example, getting enough sleep, frequent exercise, good nutrition and hydration can help you detox in an optimal way. But, ultimately, there’s not much you can do to change how fast your body expels drugs. 

Treatment for Substance Use Disorders

Flexeril is usually prescribed for short-term use over two or three weeks. It isn’t habit-forming but misuse does occur. People also take the drug with other substances in potentially harmful combinations.  

Stopping use may bring about withdrawal symptoms, but they are mild compared to those linked to benzodiazepines. 

If you or someone you know is struggling with a dependence on substances, help is available. We highly recommend seeking treatment as a way to regain control of your life.

Health professionals can supervise your detox in a safe inpatient setting if necessary. Treatment includes therapy. Counselors provide support, guidance and information to prevent relapses and sustain sobriety.

A happier and more stable life is possible. Contact Bedrock Recovery Center to discuss the best options for you.