Now Reading
How accurate are modern at-home drug tests?

How accurate are modern at-home drug tests?

If you’re applying for a particular job, life insurance, or government aid, you might have to take a blood test. Usually, this isn’t a big deal unless you’re a drug enthusiast that likes to indulge in certain mind- altering pleasures from time to time.

At-home drug test kits allow you to test yourself and monitor the progress of your detox. They’re a risk analysis tool that determines whether or not your sample is clean enough for laboratory testing. And when facing a risk of being caught, you want your at-home drug tests as accurate as possible. Today we’ll discuss the accuracy of at-home drug tests and what are their possible downsides and weaknesses. When testing yourself or somebody you hold dear, it helps to be acquainted with the possible false-positive results at-home test kits may provide.

Types of drug tests

Before we dive into the subject of at-home drug test accuracy, let us briefly talk about different types of lab tests. And when it comes to laboratory drug testing, drug tests are categorized according to their invasiveness, accuracy, and cost.

The most accurate and highly invasive drug test is the blood test. However, despite their high accuracy, blood tests have their faults, which is why they’re less common than the urine of hair testing. For example, blood tests have a significantly shorter detection window, when compared to other methods. After ingestion, inhalation of intravenous use, drugs are metabolized by the liver and expelled by the body through bowel movement, urination, and sweating, which means that the drug and their metabolites don’t stay long in your bloodstream. Though highly unlikely, cannabis can be detected up to seven days, at best, while heroin takes approximately four hours to be completely undetectable in the blood.

So, despite their high accuracy, the short detection window blood tests provide makes it hard to justify their steep price. They’re performed by lab technicians that have to take your blood, which means that they’re mostly done at the lab and very rarely on-site.

Urine Tests

Urine tests are, on the other hand, more convenient, as they’re less expensive, highly accurate, and less invasive than blood tests. Besides a relatively low price and high accuracy, urine screening also provides an incredibly long detection span. Depending on the substance, urine tests can detect drug use up to the past 90 days, which is significantly longer than other methods.

Urine drug testing is a 2-step procedure that includes a detection test and a confirmatory test. A detection test serves to detect the presence of drugs using immunoassays, measuring the presence or concentration of drugs in a solution. These tests can be bought as an at-home drug testing kit, which we’ll talk about later in the article.

If the detection test confirms the presence of drugs, the sample is submitted to confirmatory analysis. Confirmatory tests use gas chromatography-mass spectrometry, a more thorough analytical method to determine the concentration of drugs in a sample solution. If the concentration of drugs exceeds a cutoff level, the test is considered positive, which means you’ve failed a drug test. If the concentration of drugs and their metabolites doesn’t exceed the cutoff level, you’ve successfully passed a drug test.

Hair Testing

at-home drug tests

Hair testing is a pricier method of testing for drugs; however, it’s relatively noninvasive, highly accurate, difficult to cheat, and offers 90 days of detection time. It’s also a 2-step process, similar to urinalysis, but instead of urine, lab technicians chemically dissolve your hair to create a sample suitable for testing. Hair testing is always done in a lab, as it involves complex chemical procedures. However, sample collection can be performed by anyone, which is why you can purchase a hair test kit in almost any major pharmacy.

Saliva Tests

Saliva drug tests are the least invasive and most affordable method of drug testing. Testing can be done in a lab, though you can buy an on-site, at-home saliva testing kit in almost any major pharmacy. Though they provide a decent amount of accuracy, saliva tests have a detection window of 5-48 hours, depending on the substance.

The accuracy of modern at-home tests

To better understand how accurate are at-home drug testing kits, we spoke to Jonathan Hardy from, and he said: “Yes, top-quality at-home drug test kits are highly accurate, though they are subjected to limitations of field testing.” In other words, though highly-accurate, at-home kits only provide a “yes” or “no” answer to the presence of drugs, which may still be a false positive. This type of testing is almost the same as initial testing performed by the lab and is subject to error. That’s why laboratories use second, confirmatory analysis methods, like GC/MS method.

See Also

At-home drug test kits, as Mr. Hardy noted, come with their set of limitations, like the absence of confirmatory testing. And immunoassays used in urine test strips, which are sold as an at-home testing kit can return false positives due to several reasons. Because of those false positives, approximately 1 out of 100 people will test positive for drugs he or she hasn’t used.

See Also: How To Pass A Drug Test For Marijuana

For example, the painkiller ibuprofen can cause a test to show positive for weed, benzodiazepines, or barbiturates, as can certain foods and drinks. Nasal congestions sprays and cold remedies may register as amphetamines, which is why labs don’t test people that are coming down with a cold. At-home hair drug tests are slightly different as they only feature a sample collection kit, while the lab performs the actual testing of the sample. In most cases, after you’ve collected the hair sample, you’re supposed to mail it to the lab. The lab will then perform the immunoassay and GC/MS tests to confirm the presence or absence of drug metabolites within the sample.

At-home hair drug test kits are the most accurate at-home type of testing, as the lab actually performs it. It’s followed by urine sample testing, which might return a false positive, and saliva testing, which is accurate but features a narrow detection window.


We conclude that at-home test kits are accurate up to 99%, depending on various factors. However, at- home test kits differ from a lab analysis and aren’t in any way a substitute for more thorough, comprehensive drug testing methods.

At-home hair drug testing kits provide the highest accuracy among at-home test kits but also feature the highest price. Your best-value products are at-home urine test kits, as they’re perfectly balanced between accuracy, invasiveness, and cost.