By Edmund Murphy

Last updated: 06 June 2024 & medically reviewed by Dr. Jenni Jacobsen

There are many types of drug tests used to collect samples, and knowing which ones are used in which scenarios can be confusing. This guide explores the different drug test sampling methods, when they are used, and what substances can be detected.

Types of Drug Tests

What are the different types of drug tests?

There are four primary types of drug toxicology tests used in the United States, with others that are only used to test specific substances or as part of home testing kits. The primary forms of drug tests are urine, blood, saliva, and hair follicle; with sweat, residue, and breath being used in more specific scenarios.

Urine testing

Urine testing or urinalysis testing is the most common form of drug toxicology test used in the US owing to its ease of use, noninvasive administration, low cost, and high accuracy. 10 or 15-panel urine tests can detect a wide range of drug metabolites such as THC (marijuana), amphetamines, opioids, steroids, alcohol, and cocaine. Urine tests are commonly used in pre-employment drug tests.

The immunoassay (the agent in urine tests that screens for substances) will be able to detect the presence of specific drugs in the system if they are above the cutoff threshold. This means that if traces of substances are in urine but are below the threshold, the test will yield a negative result. 

If using a urine test to screen for a specific drug, a more specific screening process may be used, such as liquid chromatography, chromatography, or mass spectrometry. 

Hair follicle testing

Hair follicle testing is often used to determine long-term drug use. Drug metabolites will cling to hair follicles and will remain there for up to 90 days. Metabolites detected near the tip of the follicle determine use was longer ago than those found at the scalp. Hair testing is preferred for offering a semi-permanent record of drug use and because it is difficult to tamper with or influence results.

Blood testing

Blood drug tests boast the highest accuracy of all drug tests. Despite their precise nature, blood tests are rarely used outside of medical settings due to their invasive nature and short time frame for accurate detection.

Saliva testing

Saliva testing (oral fluid testing) can offer accurate results for drug detection of specific substances within a short time frame (often no more than 48 hours). However, they are not commonly used for random screening as they don’t detect certain metabolites such as THC.

Sweat testing 

Sweat testing for drugs is done through the application of a patch to the upper arm, lower back, or midriff that collects sweat over a period of time and detects drug metabolites. Environmental contaminants cannot get through the film, and the adhesive cannot be reapplied once removed to prevent tampering. 

Residue testing

Residue testing is typically performed as part of a home testing kit or at airports. Home test kits typically come with a swab that can be wiped on belongings to pick up drug residue. The downside of these tests is that they can not identify direct use, as any drug residue may have ended up on a person's belongings without them knowing.

Breath testing

Breath testing is performed via a breathalyzer, a handheld device that can detect blood alcohol volume via molecules in the breath. This type of test is typically only used by police and other law officials when pulling over people who have committed a driving offense and who are suspected of being drunk (DWI). They can also be installed in cars as immobilizing devices, meaning the car will not start if alcohol is detected in them. 

What is the most common type of drug test?

Most situations that require a drug test will use a urine toxicology test, meaning a sample of an individual's urine is used to test for specific drugs. Urine drug tests are favored by most as they are readily available, low cost, easy to learn how to use, and can yield accurate results in a matter of hours.[1] Most employment drug testing scenarios will use urine tests, though the legality around this differs between states. As with other types of drug tests, the amount of time a urine drug test takes to identify substances can vary depending on the following:

  • The drug being tested for

  • How much was used

  • How long a person was using before testing

  • Physical attributes (height, weight, gender, age)

Read here to learn more about how long substances stay in your system.

What drugs show up on a drug test?

There are many different drugs that show up in drug tests and they can be tailored to meet specific requirements for certain drugs. A regular 10-panel drug test will screen for:

Screening panels can range from 3-panel up to 25-panel, with each panel denoting a different drug that is being screened for.