The 4 Best At-Home Drug Tests of 2023

Interpreting At-Home Drug Test Results

Interpreting the results of your at-home drug test depends upon the type of test used and whether the at-home test kit included laboratory confirmation testing.

For self-test kits and other at-home drug tests that do not include confirmation testing, results are often interpreted by checking the test strip for the presence of a colored band according to instructions in the test package. Possible test results include:

• Positive: A positive result on an initial drug test provides only preliminary evidence of drug use and requires confirmation testing. A positive result does not mean that you are currently intoxicated or have a substance use disorder.
• Negative: A negative result indicates that no evidence of drug use was detected in the sample. A negative test applies only to the drugs included in the test. A negative result can occur if you aren’t using drugs, if you last used a drug outside of the timeframe of the detection window, or if the test kit was expired.
• Invalid: Self-test kits usually have a way of indicating invalid test results. In many tests, checking the validity of the test result requires looking for the presence of a specific colored band on the test strip.

For self-collection kits and other at-home drug tests that include confirmation testing, test results are provided by the laboratory. Results often include information about the specific test conducted, the amount of a substance that was found, and the laboratory’s interpretation. Interpretations of laboratory test results include:

• Positive: A positive test result means that the confirmation testing found levels of drugs or drug metabolites in the sample that were above the laboratory’s established cutoff value. A positive result typically specifies which drug or drugs were detected in the sample.
• Negative: A negative confirmation test indicates that no evidence of the drug use was found or that the amount of drugs or their metabolites did not exceed the laboratory’s established cutoff value. As with initial testing, a negative confirmation test may indicate that you haven’t used the drugs included in the test or that you last used drugs outside of the detection window.
• Invalid: An invalid result means that the test was not able to identify whether drugs were present in the sample. Invalid results may be reported for many reasons including evidence of tampering or adulteration that occurred during the collection process. Many laboratories provide information about why a test was determined to be invalid.

With self-tests and self-collection tests, there are several factors to consider that can affect the accuracy of the results.

False positive results occur when a drug test is positive even though you haven’t used the drug that the test is designed to detect. False positive results may occur because certain foods, beverages, supplements, and medicines can affect test results. For example:

• Consuming poppy seeds may cause false positive results for opioids.
• Taking antidepressants and other medications can cause false positive results for amphetamines or opioids.
• Using cold medicines can cause false positive results for PCP.
• Eating foods containing hemp and taking some over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs) can cause false positive results for marijuana.

False negative results occur when a drug test is negative even though you have used the drug that the test is designed to detect. False negative results may occur due to improper sample collection, expired test materials, or drug use that falls outside of the test’s detection window. Misleading results may also occur due to use of a new or modified version of the drug, or because of tampering in which the test sample is adulterated or substituted before testing.

Another common reason for misleading drug test results is that many tests aren’t able to detect all drugs in a certain class. For example, many amphetamine tests aren’t able to detect MDMA, MDA or methamphetamine. Other potential drugs of abuse that aren’t commonly available in initial drug tests include:

• Meperidine and fentanyl
• Lysergic acid diethylamide (LSD)
• Gamma hydroxybutyrate (GHB)
• Mescaline
• Inhaled hydrocarbons

If you have questions about the accuracy of at-home drug testing, it’s important to discuss your concerns with a doctor or health professional who is experienced in interpreting drug test results.

Do I need follow-up tests?

After a self-test or another drug test that doesn’t provide confirmation testing, follow-up testing is necessary to confirm positive test results. This is especially important in situations in which a positive test result could negatively affect a person’s life, such as in a legal case or employment testing.

If a confirmation drug test is positive, a health professional may follow-up by evaluating the patient for a substance use disorder. An evaluation for a substance use disorder involves asking the patient several questions to assess the pattern and effects of their drug use.

Problematic or unhealthy drug use can lead to a variety of health risks, including addiction. Addiction is a complex disease that is marked by drug-seeking behaviors and drug use that is difficult to control despite negative consequences. Effective treatment is available for drug use and addiction.

Questions for your doctor after at-home drug testing

It may be helpful to consider the following questions when discussing your at-home drug test results with your doctor:

• Can you help me understand the result of my at-home drug test?
• Do you recommend any follow-up or confirmation testing?
• What other reasons could there be for this test result?

At-home drug testing vs. drug testing in a medical setting

An important difference between at-home drug tests and drug tests conducted in a medical setting is the types of tests available.

Most at-home drug tests are self-tests, which mean that they provide only preliminary results. Follow-up confirmation testing by a laboratory is necessary to confirm the results of initial self-tests. Some self-test kits come with materials needed to mail the sample to a laboratory for confirmation testing. At-home self-collection tests often include confirmation testing in the cost of testing.

Laboratory drug testing is most appropriate when reliable test results are needed, especially in situations in which there are consequences for a positive test result. Health care providers take several steps that aren’t possible with at-home tests to ensure that testing is accurate and that the sample is not tampered with. These steps include:

• Evaluating whether any medications or supplements may affect test results
• Providing tamper-proof packaging
• Monitoring or observing sample collection
• Preserving evidence through tracking the sample’s chain of custody