What Causes False Negative Drug Test?

What Causes False Negative Drug Test – A false negative is any time that under normal conditions a drug test would be positive for an individual but for some reason results are negative.

An instance would be a patient that is prescribed Oxycodone that takes his medication constantly as prescribed but has a negative drug test during his doctor visit.

In maximum cases, this is triggered by the patient either decisively or accidentally altering their urine sample.

What Causes False Negative Drug Test?

What Causes False Negative Drug Test

The most common false negative drug test is owed to water loading.

What are False Negatives from Water Loading & Adulteration?

Water loading is the procedure where a person drinks an extreme amount of water prior to giving a sample. Urine that is clear with no yellow tint is typically indicative of water loading.

You will need to perform separate adulterant tests for Creatinine, pH, and protein levels to show that a test has been diluted by a subject ingesting an extreme quantity of water.

Without adulteration testing pure water will show negative on a drug test assay because the tests are only destined to detect the presence of a certain drug or metabolite in a substance, not to detect if the substance is a legal sample.

Subjects can just add water to their urine, but to fool a witness they will ingest an excessive amount of water to dilute the urine that comes from their own body.

There are numerous products existing that claim to help users pass urine drug screens. These products range from nothing more than fortified tea that dilutes your urine to products that claim to seal in fat cells for numerous hours.

Many of these products will speed up the timeframe in which a person can pass a urine screen even if it’s for no more reason than they’ve diluted their urine.

What are False Negatives from Improper Drug Test Selection?

An error made by organizations conducting drug tests is improper test selection. Every organization will have its own considerations when selecting a testing device, but some drug tests will not detect every illicit substance that people assume.

  • Semi-Synthetic Opiates

Numerous times, a doctor recommends their patient oxycodone or another semi-synthetic opiate but uses a 5-panel drug test that only has a test for opiates.

The doctor has seen positive tests for opiates from his patients that are given oxycodone, but his new patient tests negative.

One study found that oxycodone was noticed in 12% of opiate immunoassay tests, and many other synthetic or semi-synthetic opiates also require a special test for accurate results. 

  • Benzodiazepines

Maximum assays for benzodiazepines detect their presence in the urine by testing for nordiazepam and oxazepam, the chief metabolites of most benzodiazepines.

Agents that follow a different metabolic pathway, such as triazolam, alprazolam, clonazepam, and lorazepam, have poor cross-reactivity with the examiner due to the absence of these metabolites and so often produce false-negative results.

Some doctors prescribe diazepam, oxazepam, and temazepam instead to lessen lab confirmations.

What are False Negatives from Very High Cut-off Levels?

If your drug tests have high cutoff levels it is more probable for a user that has lately ingested drugs to produce a negative result.

The National Institute of Drug Abuse and the Substance Abuse and Mental Health Services Administration publishes suggested cutoff levels for drug testing which most companies follow.

Lots of other federal agencies publish their own standard cutoffs (everyone from the Department of Transportation to the Nuclear Regulatory Commission) that are typically based on federal recommendations.

Even though the federal government issues its own guidelines laboratories and manufacturers can create products that use whatever cutoff level they deem appropriate and the federal guidelines do change from time to time.

For example, opiates and morphine have been two extensively used cutoff levels since the early 2000s because so many people were failing employment tests because of the popularity of poppy seed muffins.

The reference soared from 300ng/ml to 2000 ng/ml. The popular tests will use this recommendation to stay compliant with as numerous federal regulations as possible, but the high-sensitivity tests are still available.

  • Faulty Device

Since the costs of a failed drug test can be so severe there is a great deal of work and investment that goes into quality control for drug test devices. Still, there are always some faulty tests or batches of tests that slip through. If you have numerous tests in a row that give unpredicted results you should consider that the tests might be faulty.

It’s very inexpensive and easy to use a 2nd drug test if a subject says that their results aren’t precise. Our drug test cups are planned to alert the user when there is a problem with the device itself.

The control line can watchful you for tampering, a faulty test, and some systems of improper collection. Any test that does not show a control line is unacceptable and can specify anything from a faulty test to tampering.

You need to keep in mind that a 12-panel drug test is truly 12 individual tests; most of the time a faulty device means only one of the strips is faulty.

A convincing percentage of faulty tests is expected in this industry, which is why we offer a 100% satisfaction guarantee that covers any faulty devices and any extra tests you use to troubleshoot a possible faulty test.

How can you limit the likelihood of false negatives in your drug testing program?

Understanding that a false negative is an option and the likely causes is the first step in stopping them. Assembling and storing data can be a vital part of investigating unexpected or suspicious results.

With sufficient knowledge and proper analysis, many drug test results that are contradictory to expectations can be reconciled and explained. Here are some other strategies you can use to limit the likelihood of false negatives in your drug testing program.

  • You can use a 12-panel drug test to cover many of the synthetic and semi-synthetic opiates
  • You need to Understand the cut-off levels and detection times for the tests you are using.

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