Although the current technological advances in science are outstanding, lab tests cannot ensure 100% accuracy. On the bright side, the chances of getting inaccurate drug test results are low. Keep reading to learn more about drug testing and the common causes of inaccurate lab results.

The Importance of Accurate Drug Test Results and Avoiding a False Negative

The main purpose and benefits of drug testing come down to safety:

  • Safety in the Workplace: Through drug testing, employers can promote a healthy workspace. Likewise, testing for drugs aims to protect employees, clients, and even property goods. Also, testing regulations can reduce poor work performance due to drug use in employees. 
  • Safe Social Settings: Screenings are crucial for the rehabilitation of individuals struggling with drug abuse. 
  • Health Concerns: There are drugs ,  such as opioids ,  that have gained recognition for their effectiveness in treating severe pain. However, people must be cautious when using these drugs. Monitoring drug use through lab tests is crucial to maintaining good health. 

What Causes a False Negative Drug Test Result? 

A false negative occurs when active drug users get a negative drug test result. Common circumstances that lead to a negative result despite the ongoing drug use are:

  1. The Window of Detection Ends Prior Drug to Testing

Drugs stay in the body for a specific time. Only during this timeframe, known as the window of detection, can tests detect drugs. 

The window of detection depends on the screening method and the type of drug. Two common types of tests are:

  • Rapid detection: aim to detect substances right after use. The detection window is brief , about 24 to 48 hours after use, depending on the drug. Some examples of rapid detection methods are blood tests and saliva tests. 
  • Long-term detection: detect past use. Follicle hair tests can detect most drugs for up to 90 days after use. Also, urine drug tests can detect cannabis from 1 to 30 days after use.

2. Testing Panel Limitations to Detect Certain Substances

Currently, urine drug tests can detect almost every substance. However, there are limitations to urinalysis and other drug tests. For example, standard drug testing panels are unable to detect synthetic cannabinoids. Also, urine and blood screenings cannot detect inhalants, since these substances are eliminated throughout the lungs. 

3. The Drug Levels Are Below the Detection Limits of the Screening

Some tests cannot detect a substance below a certain threshold. An IA drug test detects substances through the analysis of antibodies. The main purpose of IA drug tests is to rule out false-positive results. However, if the drug levels are low, an IA drug test may lead to a false-negative result. Another type of test, chromatographic testing, is highly sensitive and is more likely to provide accurate results.

4. Adulterations in Biological Samples

Drug abuse is a sensitive issue. Patients may try substituting or adulterating specimens to get a negative result.

Here are some ways in which the contamination and adulteration of specimens can happen:

  • Urine Drug Test Adulteration: Since urine tests require privacy, patients may try to substitute specimens. To prevent this, labs can implement proper specimen collection techniques. For example, some labs temperature test the sample right after collection.
  • Contamination of Sweat Specimens: During a sweat test, patients need to wear a skin patch for 7 to 14 days. During this time, intentional or unintentional patch contamination may occur.
  • Oral Fluid Contamination: Our oral cavities may contain food residues, bacteria, and microorganisms. The natural environment of mouth cavities may lead to contamination in the specimen, interfering with the drug screening results. 

At Soteria Screening Laboratories, we take strict measures to reduce the probability of false-negative drug testing results. Call (202) 679–6670 or visit us online to learn more or order a test today. We are here to help.

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