What is the difference between a positive and non negative drug test?

Drug testing is a common practice in many industries, schools, and organizations to ensure safety and compliance with regulations. It involves analyzing a person’s biological sample, such as urine, blood, or hair, to detect the presence of drugs or their metabolites. The results of a drug test can be either positive or non-negative, but what is the difference between the two?

Positive Drug Test

A positive drug test means that the person being tested has drugs or their metabolites in their system. This result indicates that the person has recently used drugs, and the amount detected is above the predetermined threshold set by the testing facility. A positive drug test is considered a fail, and the consequences may vary depending on the purpose of the test.

For example, in the workplace, a positive drug test may result in termination of employment, while in sports, it may lead to disqualification from competitions. In some cases, a positive drug test may also have legal implications, such as in criminal cases or custody battles.

Non-Negative Drug Test

A non-negative drug test means that the initial screening test has detected the presence of drugs or their metabolites in the person’s sample. However, it does not necessarily mean that the person has used drugs. There are several reasons why a drug test may yield a non-negative result, including:

1. Prescription Medications: Some prescription medications can cause a non-negative result on a drug test. For example, opioids, benzodiazepines, and amphetamines are commonly prescribed for medical conditions, but they can also be abused. If a person is taking these medications as prescribed, they may test non-negative for these drugs.

2. Over-the-Counter Medications: Certain over-the-counter medications, such as cold and flu remedies, can also cause a non-negative result on a drug test. These medications may contain ingredients that are chemically similar to drugs of abuse, leading to a false positive result.

3. Dietary Supplements: Some dietary supplements, particularly those marketed for weight loss or bodybuilding, may contain substances that can cause a non-negative result on a drug test. These supplements may contain stimulants, steroids, or other substances that are banned in certain sports or professions.

4. Contamination: In some cases, a non-negative result may be due to contamination of the sample. This can happen if the person being tested accidentally touches the sample with their hands, or if the sample collection process is not done correctly.

What Happens After a Non-Negative Result?

When a drug test yields a non-negative result, the sample is sent for further testing, usually through a more sensitive method called gas chromatography-mass spectrometry (GC-MS). This test can differentiate between drugs and their metabolites, as well as identify the specific drug and its concentration in the sample.

If the GC-MS test confirms the presence of drugs, the result is then considered positive. However, if the GC-MS test does not detect any drugs, the result is considered negative, and the non-negative result is considered a false positive.

In some cases, a non-negative result may also prompt further investigation, such as an interview with the person being tested or a request for a retest. This is to ensure that the result is accurate and to rule out any possible explanations for the non-negative result.


In summary, the main difference between a positive and non-negative drug test is that a positive result indicates the presence of drugs in the person’s system, while a non-negative result requires further testing to confirm the presence of drugs. It is essential to understand the difference between the two to avoid false accusations and to ensure that the results are accurate. If you have any concerns about a drug test result, it is best to consult with a medical professional for further clarification.

What is the difference between a positive and non negative drug test?

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