Why doesn’t my Klonopin show up on a drug test? 

Why doesn’t my Klonopin show up on a drug test? 

Klonopin (Clonazepam) may not show up on a drug test because of the following reasons:

  • Your dose might be too low 
  • The drug was not a part of the panel of drugs to be tested 
  • You took your last Klonopin dose hours before going for the test 
  • Your drug testing procedure is giving a false negative

Your dose might be too low 

If you are taking a very low dose of Klonopin, it may not show up on a drug test. Klonopin is one of those Benzodiazepines known to not show up at usual therapeutic doses. However, it also depends on the drug testing procedure you’re going for – that we will discuss shortly. 

The drug was not a part of the panel of drugs to be tested 

Klonopin may not show up on a drug test if it is not focused on Klonopin or if the medication is not included in the panel of drugs to be tested. 

This is common in the majority of cases where more dangerous and potent medications are of concern. Even if Benzodiazepines are included in the panel, Klonopin may not show up. However, other Benzodiazepines can show up in such tests. 

You took your last Klonopin dose hours before going for the test 

Klonopin has a long half-life of about 20-50 hours and can stay in your body for several days. However, its concentration may become low enough to not be detected within 3-4 days. 

This is more of a possibility if you’re on a low dose of this medication. This is also common for people who use Klonopin intermittently as a sleep aid. 

Your drug testing procedure is giving a false negative

Klonopin might not show up on a drug test because of the low accuracy of the testing procedure. Drug tests like urine immunoassays are known for causing false positives. 

However, these tests can also give false negative results in some cases. Even if Benzodiazepines are to be tested, your drug screening may not detect Klonopin at all. Other testing procedures which are considered more accurate are expensive and not everyone can go for them. 

These cheaper tests are more feasible for people and that’s why they are frequently used – despite the not-so-accurate results. On the contrary, testing procedures like Gas Chromatography – Mass spectroscopy, are much more reliable because of how they work (1).

Final words

Klonopin does show up in a drug test generally, and since Benzodiazepines can be used for addiction and abuse, these meds are included in the panel of drugs to be tested. All Benzodiazepines show up the same in a drug test. However, these tests may not show accurate results sometimes. 

It is always best to inform the drug testing authorities about your current prescription medications and OTC meds as well. 

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References

1.-

Ramoo B, Funke M, Frazee C, Garg U. Comprehensive Urine Drug Screen by Gas Chromatography/Mass Spectrometry (GC/MS). Methods Mol Biol. 2016;1383:125-31. doi: 10.1007/978-1-4939-3252-8_15. PMID: 26660182. Available from: https://pubmed.ncbi.nlm.nih.gov/26660182/