Background Checks
Manage your employment screening program easily and more efficiently with GoodHire’s award-winning advanced platform.
Access our full library of content to learn about hiring trends, screening compliance, and how GoodHire works.


Negative Or Positive? How To Read Employees’ Drug Test Results

Illustration of a candidate's drug test results that shows negative and positive results.

Drug testing can help ensure a safe and productive work environment and reduce accidents and injuries. But since drug tests often screen for multiple substances, hiring managers and employers may have trouble understanding the results.

We’ll explain what a drug test includes, how it’s performed, how to read the results, and what to do if a candidate or employee tests positive.

For many employers, drug testing is a crucial part of the hiring and employment process and is well worth the drug test cost. Companies need to ensure a safe and productive work environment and reduce the risk of accidents and injuries on the job. 

For many jobs and agencies, pre-employment drug testing is required for a job, as is regular drug screening to ensure employees remain free of substance abuse on and off the job.

However, because drug tests often screen for multiple substances, it may present some challenges for hiring managers and employers tasked with understanding a candidate’s drug test results. How do you read drug test results from a lab? What do they mean? How do you understand drug test results? 

GoodHire is sharing what you need to know about employee drug testing—and the results.

Understand What The Drug Test Includes

To best understand how to read drug test results, you also need to know what you’re testing for. GoodHire’s Drug-Testing Suite offers several different options for drug screenings to meet your company’s drug policy while remaining compliant with applicable federal and state laws. The four most common drug screening panels include:

Drug test options

Drug Screen
4 Panel
5 Panel
8 Panel + MQL
10 Panel *

* Quick Test is available, however it excludes Methaqualone (MQL) and tests for Methamphetamine in its place.

Each drug that’s tested has a detection window, which is the length of time a drug remains in a person’s system and can be detected on a test. 

Why is this important? Because it means a negative drug test result doesn’t necessarily mean drug use hasn’t happened recently. These detection windows last anywhere from a couple of hours (alcohol or heroin metabolite) to several days and weeks (benzodiazepines, PCP, and marijuana if used chronically).

Understand How The Drug Test Is Performed

There are several different ways a drug test can be performed, but because drug-testing laws vary from state-to-state, certain testing methods may be prohibited in some states. 

Urine drug test results analysis

The most common drug test is a urine analysis, which is the method used in GoodHire’s Pre-Employment and Employment Drug Testing. If a urine test is positive for a substance, it’s important to remember that it doesn’t necessarily mean an employee or candidate was under the influence at the time of the test. 

Instead, it means the test detected the presence of the drug within the detection window. It’s also important to note a urine test doesn’t detect the amount of drugs present in a person’s system—just that it is present.


Breathalizers are commonly used for employees who work for companies regulated by the US Department of Transportation (DOT). These can detect how much alcohol is present in the blood at the time of the test and may be used in situations where there’s suspected intoxication on the job. 

For this type of test, the person blows into a device that immediately reveals their blood alcohol concentration (BAC) to determine whether they’re under the influence of alcohol.

Blood test

Like a urine test, a blood test determines whether drugs are in a person’s system. This method does measure the amount of drugs present at the time of the test. The downside? Blood tests are a bit more invasive and can take more time to produce results.

Hair sample

Some employers may require employees or candidates turn over a hair sample, which can detect traces of drugs in a person’s system for a much longer period of time—up to 90 days. A hair sample drug test does not detect whether a person is under the influence at the time of the drug test and cannot test for alcohol.


Saliva is usually collected by swabbing the inner cheek of an employee or candidate. This type of test can detect trace amounts of drugs and alcohol.

Understand The Drug Test Results

Every drug test result through GoodHire, regardless of whether it is positive or negative, is interpreted and confirmed by a Medical Review Officer (MRO). MROs are highly-trained medical specialists that read and confirm results. Every candidate who has a positive lab result has the opportunity to speak with an MRO before a report is given to the company.

Although those results produce a simple positive or negative, there are several things employers may need to consider further. That’s because tests don’t provide additional context that may be necessary when making disciplinary or hiring decisions. For example, positive drug test results don’t provide information like:

  • How a drug got into a person’s system
  • How much they took
  • When exactly they took it (estimates can be made based on detection windows)
  • Whether they’re currently impaired (with the exception of a breathalyzer)
  • Any information about a potential addiction

It’s also important to note that with each drug test, there’s a minimum measurement required for each drug to help determine a positive or negative result. Also called the cut-off level, this can help employers better understand the chance of false-positives. For example: 

  • If a cut-off level is low, employers may receive more false-positives because of trace amounts of a substance (like eating poppy seeds)
  • If a cut-off level is relatively high, some traces of drugs may go undetected

Finally, employees and candidates may also be taking prescription drugs that can result in a false-positive drug test, including:

  • Over-the-counter (OTC) cough suppressants
  • Allergy medications
  • Sleep aids
  • Drugs to treat hypertension and diabetes
  • Blood pressure medications
  • ADHD treatments, and more

Because of this, employees and candidates are encouraged to bring in any prescription drugs and inform the drug testing lab of OTC medicines they are currently taking or have recently taken.

Understand Next Steps

When employers receive positive drug test results back from an employee or candidate that constitute a failed drug test, the proper next steps must be taken to ensure compliance with federal and state laws. 

These steps are outlined by the Fair Credit Reporting Act (FCRA), which ensures that candidates and employees: 

  • Have the right to be informed when a background check or drug screening will be conducted
  • Must sign a consent form
  • Have the right to review the results and correct any errors
  • Have the right to know when those results are used in decisions about their employment

Employers must also have a written drug policy in place and adhere to those guidelines.

Depending on the location of your company, each state has different laws when it comes to drug testing results and the impact on employment and termination. Some states allow employers to use the results as grounds for terminating employment.

In contrast, some allow employees to contest or explain a positive drug test result within a certain number of days. For example, in Louisiana, employers cannot terminate an employee based on a first-time positive drug test. Other state laws may regulate areas such as:

  • Disciplining an employee for refusing a drug test
  • Accommodating employees who wish to enter drug treatment programs
  • Suspending an employee vs. firing, and more

No matter an employee or candidate’s unique situation, though, you should always comply with your company’s drug policy, and both state and federal employment drug test laws to ensure compliance, fairness, and consistency.

Read & Understand Drug Test Results Through GoodHire

Reading and understanding drug tests may be as simple as looking at the words ‘positive’ or ‘negative,’ but the drug-screening process is much more complex than that and requires compliance at every level. 

To minimize the risk of noncompliance for your company and to uphold fair hiring practices, use an accredited Consumer Reporting Agency (CRA) like GoodHire for pre-employment and periodic employment drug screenings.

Looking For Employment Drug Tests?

GoodHire makes it easy to get started.

Illustration showing GoodHires drug test option

The resources provided here are for educational purposes only and do not constitute legal advice. We advise you to consult your own counsel if you have legal questions related to your specific practices and compliance with applicable laws.

About the Author

Ashley Blonquist is a former news journalist. She writes about GoodHire’s employment screening services and how employers use them to make informed hiring decisions.