Last updated : July 14, 2025
Home drug test kits make drug testing easier and more affordable for small business owners. Parents who worry their child is using drugs also purchase them. The directions are easy to follow, but reading the result can be confusing when a faint line appears in the result section.
Home drug tests are pass-or-fail litmus strip tests. Simply dip the strip into a urine sample. The result is visible in minutes. The instructions say that if no line appears in the result section, it indicates that the urine tested positive for drugs. If a line appears in the test area, the urine tests negative for drugs. Parents—and drug-using employees who are self-testing to see where they stand—often become unnerved, however, when the line is so faint that it’s nearly non-existent.
Some wonder if that means that there was just a “teensy tiny” amount of drugs found in the specimen.
Negative never equals positive
Determining the result of a home drug test is cut and dried if you stick to the big picture. The tests are designed to be either pass or fail. There is no in-between. When there are two colored lines in the test’s result section, the sample tested negative for drugs.
The top of the test region is generally marked with a “C” to indicate it’s the control region. There should be a line in the control area. The second line will appear in the test region—some tests determine the test area with a “T” rather than a word.
If there is a colored line in the control region and no line in the test region, the drug test is positive. If a line appears in the test region—even a very faint line—it’s a negative result.
Fretting parents and nervous employees often worry that a faint line indicates a small amount of the drug remains in the system. However, the test is a pass or fail, so no matter how faint the line is in the test region, it’s a negative result.
Positive results
To obtain a positive result on an over-the-counter urine drug test requires that a specific amount of the drug be present in the sample. When that is the case, there is no line at all.
The minimum level required to obtain a positive result differs depending on the drug type. No matter what drug is on the test panel, if the predetermined level—or higher—of the drug is detected in the specimen, no line shows up.
Laying it on the line
Every drug test has a pre-set detection level, which should be the same level set by the Substance Abuse and Mental Health Services Administration (SAMHSA). It’s best to choose a home drug test that is FDA-approved. This determines that the pre-set test levels are correct. However, no test purchased over the counter detects the specific amount of a drug because, as mentioned above, it’s a litmus test. The method is either pass or fail.
There are some valid reasons for a faint line to appear in the test section of the drug test. Let’s take a look at them.
Urine composition
Urine excretion cleanses the body of unnecessary substances. Some of which may cause a faint line to appear on a drug test.
They include:
- Medication intake
- Fluid consumption
- Overall health
OTC medications
Over-the-counter (OTC) medications are available for a myriad of maladies. Some of them are chemically similar to the illicit or abused drugs identified on drug screens. If a similar compound is present in the urine, a faint line is likely to indicate that.
Consider the source
Drug tests processed at a laboratory undergo a series of tests—if warranted. Most drug tests are negative, therefore, the first test completed at the laboratory is a litmus test. If the result is negative and nothing seems out of the ordinary, there isn’t any further testing.
Laboratory technicians are experts at reading drug test results. If something about the sample raises a red flag, they are trained to look deeper. A faint line on the litmus test result doesn’t even earn a second glance. The test is immediately deemed negative.
A nervous employee is likely to look twice, though. Parents—or anyone else—who need peace of mind can contact a SAMHSA-approved laboratory to determine test results. It will eliminate the concern associated with the faint line because these labs guarantee accurate results. Avoid less reputable laboratories because they may have substandard operating procedures and less attentive techs.
SAMHSA-approved laboratories earn government ratings. Subsequently, government regulations hold them to the strictest of standards. The staff is trained to be aware of the possibility of varying test results. Moreover, these labs ascertain that their sample cups and saliva test swabs match government standards. This is especially important for mandated employers. Say, those who employ the safety-sensitive workforce, for instance, mandated by the DOT.
It’s equally important for parents who need to know the truth about their child and drug use. The thought of where such a dark path leads is terrifying. Allowing a laboratory to determine whether or not a child is using drugs rather than trusting a home test kit grabbed at the local shopping center brings peace of mind.
Contact a local SAMHSA-approved laboratory to inquire about the cost and collection process. A representative will be happy to answer all your questions.
In the case of a positive result, parents can trust the accuracy and begin seeking outside help for their child immediately. If it’s the case of an employee, company protocol is followed to the letter.
The reason for drug testing
Anyone who uses drugs is putting themselves at risk.
Many illicit or misused drugs are highly addictive. Moreover, now fentanyl is in every type of street drug available. Sadly, it’s often a deadly secret ingredient. Drug cartels have it cheaply manufactured in clandestine factories in China and Mexico. Then, they smuggle the drugs into the United States.
Becoming a drug addict is not something anyone plans. It usually begins as a thrill-seeking adventure, or perhaps someone who suffers from anxiety may drink or use drugs to lessen it. Choosing to self-medicate when faced with uncomfortable situations often leads to addiction.
In case you weren’t aware of the stats, fifty percent of drug addicts are genetically predisposed to be so. Seriously, it’s in the DNA. Perhaps, they may have never used a drug in their life, but after using opioid painkillers after surgery, they found themselves desperate for more when the prescription ran out. The other fifty percent of addicts have poor coping skills.
Addiction is a disease, not a weakness. Drugs eventually change how the brain works. This leads to a loss of self-control and damaging behaviors—and, for many, death.
We must draw a line in the sand. It won’t be faint either, but bold and strong. Continued education, employers who promote drug-free workplaces, and parents who promote drug-free homes are all sound ways for us to leave our mark.
