Reading a Drug Test

On-site immunoassay, or more commonly know as urine drug testing, is used for initial screening of the presence of drugs in a person’s system. Urine drug tests are checking for a certain level, or the detection level, of the drug or drugs. These tests are qualitative and thus will not show the exact level present, only if it is over or under the detection level. The result of these tests is either positive or negative.

Drug testing is counterintuitive from other tests, such as a pregnancy test. A drug test is positive if there is no line on the test, as opposed to a line indicating a positive pregnancy test. However, there always needs to be a control line (indicated below with the line connecting the two Cs). Without a control line, the test is not working and thus not valid. A drug test is negative no matter how strong or faint the line is - remember, a line is still a line.

Reading an iCup Drug Test

As with all drug testing products, it is necessary for a line to be present in the Control Region (C). The Control Region is at the top of the iCup testing window. If this control line is not present, the test is invalid. Below the (C) line are numbers, and each number corresponds to the drug listed below that specific strip window.

Below is an iCup with all negative results. You can see that the (C) line is present, and all numbers with corresponding drugs have lines in their test regions (T). Again, a line is a line – even if it is faint. On the fourth strip, there is no line in the test region to the right of the number 3. This is because the number 3 is for the strip to its left, and there is no third drug for the test region that is blank. This is not a positive result.

The following iCup shows positive results for both marijuana (THC) and opiates (OPI). You can see that neither the third test region in the first strip nor the second test region in the second strip have lines, but all control lines are present.

About the Results

NEGATIVE Drug Test Results

A negative test result is when TWO lines (or more, in the case of multiple drug testing) of any color intensity appear. A colored line must appear in the Control Region (C) and a colored line must appear in the Test Region (T) for each drug.

Even if the line that appears is faint, the result should be considered negative. The possible shades of colored lines in the Test Regions may vary.

What does this mean?

If a test is negative, it means that the concentration of the drug in the urine sample is below the designated cutoff level set by the test. A person may still have that drug in their system, just not above the cutoff limit. For example, if a donor has 30 ng/mL of marijuana in his or her system, and the cutoff level for THC is 50 ng/mL, the donor would test negative on a drug test for marijuana. Cutoff or detection levels are suggested by SAMHSA and are used to prevent the majority of false positives for trace amount of drugs in a donor’s system. The detection levels are different for each individual drug, and most of the drug testing in the workplace uses a standard set of cutoff levels. However, law enforcement and addiction treatment programs that have a zero tolerance policy will sometimes use a lower cutoff level in their testing.

POSITIVE Drug Test Result

A positive drug test result is when ONE line appears in the Control Region (C) and NO line appears in the Test Region (T).

A positive test result means that the drug concentration in the urine sample is greater than the designated cutoff level for a specific drug; additional confirmatory drug testing may be needed. The cutoff (detection) levels for each of our products are listed on our web site.

If a positive result is indicated, check with the donor for any prescription drugs that might be cross-reacting (see chart) with the test. Keep in mind, positive drug test results should only be assumed positive and then confirmed with an alternative method such as gas chromatography/mass spectrometry (GC/MS) or high performance liquid chromatography (HPLC).

INVALID Drug Test Result

An invalid test result is when there is NO line in the Control Region (C).

The most common reasons for an invalid test are incorrect procedures, insufficient volume of the specimen, or a faulty test. Please read the test instructions again and repeat with a new test card or cup. If the result is still invalid, please contact POC Test Supply at 888-968-3088 for assistance.