Drug Testing Methods
Most people hear “drug test” and instantly think of people peeing into a cup, and for good reason. Most drug testing programs do use urine as the primary way to test for drugs. However, there are other ways to do it. Guest author, Lena Butler, describes the most common drug testing methods, their differences, similarities and the pros and cons of each in her guest post, below. Lena Butler is a health blogger and customer service representative for TestCountry, a San Diego based point of service diagnostic test service provider that offers a wide range of laboratory and instant drug and general health testing kits.
Drug Testing Methods by Lena Butler
Instant tests vs lab tests
Before we get to the bodily fluids, we have to look at these two broad categories.
Instant tests, which are also known as point of contact (POC) tests in some circles, can be done almost anywhere and done quickly. They also generally only require one or two simple tools to perform.
Laboratory testing, on the other hand, is obviously performed in a laboratory with highly sophisticated equipment. Specimens can either be collected at the laboratory or collected off site and delivered to a lab for testing.
Most drug testing programs will include both instant and laboratory drug testing. Generally, an instant drug test is performed and if the results are positive, the sample is sent to a lab for testing or the person who gave the specimen is taken to a lab to give another specimen to be tested there. This is because instant test results won’t hold up in court, so if the results are required for legal purposes, lab testing will need to be performed at some point. A positive result on an instant drug test merely detects the presence of drugs, but a positive result in a laboratory test actually confirms the presence of drugs.
The advantages of instant drug testing kits are that you get your results right away and they are relatively inexpensive. You can also get kits that test for one drug or as many as a dozen drugs at once. However, instant drug tests are occasionally prone to false positives and the results are not legally admissible.
The advantages of laboratory testing is that all the testing is handled by professionals and the results will hold up in court, if necessary. The disadvantages are the expense, as those sophisticated machines used for testing cost a lot of money to run and you will be paying for that in lab fees, plus the time it takes to get results, which could run from hours to days depending on factors like how busy the lab is.
This is why most drug testing programs will feature both instant and lab testing, to combine the advantages of both.
Types of drug testing
And now we get to the nitty gritty. The three most common ways of testing a person for drugs is via urine, saliva and hair.
Both urine and saliva have the option of using instant testing kits to collect and test a sample wherever the test is administered. Obviously, for urine tests, you need a private location to collect samples.
Hair testing has no instant option available. Although samples can be collected anywhere, the actual testing must be done at a laboratory.
Urine testing
By far the most common drug testing method for companies, pre-employment screening, sports, military and police work, urine tests can detect traces of drugs in the system for about a week or two (depending on the type of drug and other factors).
These tests involve having a person fill a cup with urine to a certain level and seeing how the urine reacts with certain chemicals. Sometimes you need to dip a testing strip in the urine or transfer some of the urine to a testing cassette. However, you can also get one-step testing cups where you can put a lid on the cup and push a button or turn a key and the test is completely performed within the cup, saving you from having to do anything with the liquid inside.
The collection of urine is obviously somewhat invasive, especially when the collection must be observed (which is the case in some organizations). And urine tests can be cheated.
Swapping in someone else’s urine for their own is one way people try to cheat, although a temperature strip or thermometer will prevent this type of cheating, as a swapped sample won’t be body temperature like a fresh sample would be. Obviously, watching the sample being given also prevents this type of cheating.
People also try to cheat by drinking excessive amounts of water or other liquids to dilute the urine sample. However, many tests can detect overly watered down samples and, on top of that, many drugs aren’t water soluble, so this doesn’t even work for a lot of drugs.
Adding some foreign substance to the sample (salt, vinegar, bleach etc.) can render it useless, but many of the current instant urine tests on the market have ways of detecting an adulterated sample like this. Laboratories will have methods in place for detecting watered down samples and foreign liquids.
Saliva testing
This involves taking a swab of oral fluid from the mouth of the test subject. It has been noted that gum chewing or cigarette smoking can potentially mess with the results of these tests, but they are generally reliable enough to tell you if further lab testing is required. The results are available in a couple of minutes and they can detect drug use from a few hours to a few days after use, again depending on the drug.
The collection process for saliva testing can easily be observed, which means cheating is virtually impossible. Plus, you don’t need the same level of privacy when you’re collecting a sample as you do with urine, meaning you can pretty much collect and test a sample anywhere and get immediate results.
Also, saliva testing will be able to detect drug use within about an hour of it being used, or even quicker in the case of some drugs.
Hair testing
The most reliable and comprehensive of the three, hair testing is impossible to cheat and hair samples, despite what you may have read, are not affected by dyes, bleaches, shampoos, changes to diet or any other cheating attempts. Hair tests can not only detect drug use up to 90 days prior to testing, but also how often a drug was used. Long hair is not required for testing. Both short head hair and body hair can be collected and used for testing, so head shavers can’t even cheat this test.
Hair testing is more expensive than both instant urine and saliva tests and there is no such thing as an instant hair test. You will either have to collect a sample and send it to a laboratory or have the sample collected at the laboratory. And unlike a saliva or urine test, traces of drugs won’t show up in a hair sample until after about a week of being used, regardless of the drug. For example, if a test subject smoked marijuana on a Friday and was to give a hair sample for testing on the following Monday, that marijuana smoked on Friday would not show up in the hair sample.
Because the testing involves cutting hair off of people, the sample collection is somewhat invasive, but the hair sample, which has to include several dozen strands, is collected from various spots, usually near the back of the head where it is the least conspicuous.
In summary, you may hear about blood being used for drug testing, and it can be, but it is rare. Urine, saliva and hair are easily the most common methods of drug testing and each has its advantages and disadvantages for drug use detection.