What can cause a false positive for Cocaine?

What can cause a false positive for Cocaine?

Several factors can cause a false positive for cocaine in a drug test. These include:

  • The use of certain over-the-counter cold and flu medications (1).
  • Certain prescribed medications, such as antidepressants (e.g., tricyclic antidepressants)
  • Coca leaf-containing products.
  • Foods containing poppy seeds.
  • Immunoassay interferences.
  • Contaminated samples

If you’re having a false positive for Cocaine without ever using it, you need to go for more sensitive test procedures like High-power Liquid Chromatography (HPLC) and Ultra-power Liquid Chromatography (UPLC). (2)

Such highly sensitive procedures can accurately detect the chemical responsible for causing a false positive test, either for Cocaine or any other controlled substance. 

How to avoid getting a false positive for Cocaine?

To avoid getting a false positive for cocaine in a drug test, it’s crucial to be aware of potential substances or factors that might interfere with the results. 

Firstly, ensure that you are not using any over-the-counter medications, such as certain cold or allergy remedies, that could contain substances similar to cocaine or trigger a false positive. Additionally, be cautious with coca leaf-containing products, as they may also lead to inaccurate results.

To eliminate the risk of false positives, inform the test administrator about any prescribed medications you are taking, as some drugs can cross-react with the cocaine test.

If you have concerns about the test’s accuracy, request a confirmatory test, such as a gas chromatography-mass spectrometry (GC-MS) test, which provides more reliable results (3). 

Lastly, maintain open communication with healthcare professionals or the testing facility, providing full details about your medical history, diet, and any supplements you are using to ensure accurate and valid drug test results.

Final words

To sum up, a number of things can cause a false positive test for Cocaine, even some medications. This is why it’s important to inform the drug testing authority about all the medications, both OTC and prescription meds, you are currently taking. 

This can help in case you get a false positive. If you have a drug test coming up and you’re concerned about getting a false positive, it’s recommended to seek professional advice.

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