How can I drug test without someone knowing?

Surface and visible substance testing can help you drug test someone without their knowing. So can drug screens using hair samples. But testing for drugs without consent is not recommended. More on drug testing without someone knowing here.

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Can you test a person for drugs without their knowledge?

The answer is yes and no. It is quite easy to test for the presence of drugs in a room or area without a person’s knowledge and it is technically possible to test someone for drug use without their knowledge, but it is not recommended. In fact, if you are asking, “Is my child on drugs?”, have someone close who is in recovery from drug or alcohol addiction or suspect that your partner or loved one is using, drug testing is best completed when consent is explicit.  And helping your husband with drug addiction (or your wife, or partner, or child) requires more than just confrontation or intervention.  Still, we discuss the particular methods for drug testing without consent here, and invite your questions about drug testing in the comments section at the end.

Surface substance testing

What many drug users (and people in general, really) don’t know is that after you handle drugs, you leave a trail of invisible drug residue on the surfaces you touch. These surfaces include: computers, phones, vehicles, clothing and just about any other surface. You can’t see this residue but you can test surfaces to see if any of it is there (which means you don’t need the person who is leaving the residue behind to be around when you test it). So how does it work?

Typically, surface substance testing involve wiping down a surface with some kind of small testing device and then instantly performing the test. Often this involves using tap water to make the test work. They all come with their own detailed instructions. You then read the test (they usually use lines like a pregnancy test) to see whether or not traces of drugs are present.

What does surface substance testing screen for?

You can get surface and visible substance tests that detect only one or two drugs or you can get more comprehensive ones that test for five or more drugs. But one thing that is important to keep in mind is that these tests will merely tell you if drugs are present on that surface. This test cannot tell you if someone is actually doing drugs (although some of them can be used to test people’s sweat for drugs). However, if you are trying to maintain a drug free household or workspace, naturally drugs shouldn’t be on any surfaces and you’ll know you have a problem if you find them.

Drug testing visible substances

A slightly different kind of test allows you to determine if a substance contains drugs. So, if you can actually see some kind of powder or some other substance that you’re not sure of, you can take a sample of it and use one of these tests to determine if it is a drug or contains any drugs. You can also test a substance you are familiar with (such as toothpaste, for example) to see if it contains drugs. Keep in mind, though, that these tests can only determine if a substance is a drug or contains drugs and not if a person is actually doing drugs.

Where to buy surface and visible substance drug tests?

There are a number of different surface testing kits and substance testing kits on the market that are relatively inexpensive. And while you do get the advantage of instant results with these kits, also keep in mind that they have expiration dates and that they have to be kept and used within a certain temperature range to maintain their validity.

Hair drug testing without someone knowing

I was a bit torn on whether or not to include hair testing in this entry but I decided to include it for informational purposes. It would be technically possible to collect samples of a person’s hair and have that hair tested for traces of drugs without their knowledge. However, this is discouraged by the laboratories that perform these tests for a number of reasons.

The most obvious of those reasons is because it is considered to be an invasion of a person’s privacy to send their hair away for drug testing without their knowledge. Another big reason it is discouraged is because there is no way of knowing 100% for sure that the hair you’re gathering from a person’s hair brush or pillow or wherever else it is collected is from the person you think it belongs to (hair travels quite well on people’s clothing and people do share things like hair brushes and pillows on occasion). Yet another reason it is discouraged is that a hair sample collected in this way won’t be consistent, unlike one collected in the usual manner.

Because I’ve already mentioned hair testing, I will give you a quick overview of it.

How do hair drug tests work?

When drugs enter an abuser’s system, they are metabolized by the body, creating tell-tale metabolites that are distributed throughout the body by blood and leaving traces in the body’s tissues, like hair follicles. The metabolites then stay in a person’s hair follicles and laboratories can detect drug use up to 90 days prior to the sample being taken (a half of an inch for every 30 days). A big advantage with hair testing is the amount of time you can test for. Ninety days will give you a pretty comprehensive picture of recent drug activity.

As far as the actual testing goes, on your end, all you have to do is collect a sample, place the sample in the collection pouch that is provided with the testing kit, seal it and send it to the lab. Each kit will come with its own detailed instructions on how to collect a sample. The laboratory will do all the actual testing.

Collecting the sample involves cutting a small chunk of hair off the person’s head as close to the scalp as possible. Anywhere from 40 – 100 strands are needed depending on the type of hair being tested. All the strands of hair need not come from the same area on the head. You can gather them from different areas. You can also use body hair.

Can you cheat on a hair sample drug screen?

No. Hair testing has some big advantages over urine and saliva testing. Probably the biggest advantage to testing via hair follicle is that it’s virtually impossible to cheat. Because the laboratory is testing the very molecules the hair is made of, no shampoo or anything else marketed to beat hair drug tests have any effect on them. Even dyes and other things that manipulate the hair don’t change it on a molecular level.

Disadvantages of testing for drugs using hair

Hair follicle testing does come with some disadvantages, though. Two of those are the time frame involved with the testing itself and also how long it takes for drug traces to show up in the hair.

Because hair follicles need to be sent to a laboratory, immediate results are not available. Typically, a lab can get results back to you between 7 – 10 days. Some labs have the option of fast-tracking your sample for an extra charge for a turnaround of only a couple of days.

Also related to time, it takes about a week for traces of drugs to show up in a person’s hair so if you suspect a person of having done drugs on a particular day, you will have to wait a while before collecting the sample.

Where to find hair sample drug test kits

There are several hair sample test kits available on the market. There won’t be much to the kits themselves, probably just instructions, something to hold the specimen, an envelope to put it in, a security label and maybe one or two other small items. Keep in mind when comparing prices that it’s the lab work that you’re really paying for, not what is included in the kits themselves.

Should I drug test without someone knowing?

The decision to drug test without consent will be yours. No type of testing, though, takes the place of good, old-fashioned open communication and mutual understanding. But it’s good to know that these tests are there if you need them.

About the author
Lena Butler is a mom, health blogger and customer service representative for TestCountry. TestCountry is a San Diego based point of service diagnostic test service provider that offers a wide range of laboratory and instant testing kit solutions including drug tests, metal toxicity, DNA paternity, food and water tests and hundreds more. TestCountry's tests are easy to use and can be performed at your home or workplace.
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