Drug Tests 101 – What Everyone Should Know About Screening

A Complete Guide to Drug Testing
A drug test, sometimes also referred to as drug screening, is any test administered for the technical analysis of biological specimen of human body (such as blood, urine, saliva, hair, sweat etc.), in order to detect the presence, or in some cases any prior use, of illicit parent drugs or their metabolites. A metabolite is basically the inactive metabolized form of a parent drug.

The drugs you did last night, at the weekend party, or even on last New Year’s eve – they can all be in your system, be it your blood, urine, saliva, or even hair, waiting to be detected either by the government, your employer, or in the worst case, your parents when they use drug testing kits for home use. That’s what makes drug testing a nightmare for any user.

What are drug tests used for?

Drug tests are used to detect the use of illicit drugs in job applicants, athletes, criminal offenders, participants of drug rehabilitation programs, and others. If illicit drugs are detected, the person usually endures some sort of consequence.

Knowledge is power. The more you learn about drug tests, the better your chances are to beat it, so let’s get started.

Only a few decades ago, the human body was shielded from the outside world just like a well-built fortress, and detecting what’s inside it was nearly impossible. Unfortunately, recent advances in science have given birth to sophisticated drug testing, a multi-billion dollar industry that exists just to shame you by revealing your wrongdoings that you thought will never be known by others.

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Types of Drug Tests

There is a wide variety of drug tests which can be divided into two major categories: doing drug testing at home and professional drug testing done by a qualified expert, usually in a sophisticated facility.

At Home

Several drug tests, such as urine test or saliva/oral fluid tests can be easily done at home. All you need to do is buy one of the home drug test kits available as over-the-counter strips, collect a sample of urine or saliva, dip the strip in the urine/saliva for the specified amount of time, and view the reading. These strips are available online as well as in stores, are fairly easy to use, and come with detailed directions. However, results from cheap drug test kits can usually be misleading and incorrect. Even if you use a high-quality kit, there are several external factors that can impact the results of the test, unless you do a lot of research, have some working knowledge of testing, and are very careful in your approach.

Are home drug testing kits accurate?

Home drug testing kits can provide accurate results if they are done very carefully. However, home drug testing kits, especially cheap ones, have the potential to be misleading or inaccurate considering there are a number of external factors that can affect the test’s results that someone doing the test at home may not know about.


Professionally conducted drug tests are more accurate, offer a deeper insight, and are more expensive. There are different types of professional drug tests including urinalysis (urine test), swab (saliva test), blood test, hair follicle test and so on.


To realize the popularity of the urinalysis, consider this fact: 90% of the 55 million drug tests performed last year were urine tests. It’s called the gold standard of the drug-test industry – no pun intended. Because most part of the drug is already metabolized, the urine test, instead of detecting illicit parent drugs, tries to detect the presence of non-psychoactive drug metabolites. For example, marijuana’s primary metabolite is THC-COOH which is fat soluble and can be detected in urine for up to two weeks. Urine testing, despite its popularity, is the easiest of all the tests to beat using a variety of tricks.

Blood Test

It’s the most invasive and the most accurate form of testing. Unlike urine test, blood test actually detects the presence of parent drugs and not their metabolites because most drugs, such as nicotine, marijuana, are instantly absorbed by your bloodstream and are easily detectable. Since these are the most expensive type of tests, they are less common and are only administered if a lot of money or law is on the line. Also, most drugs don’t stay in your bloodstream for too long. For example, marijuana becomes undetectable after a few hours of use, but in chronic users, it can stay detectable for more than 24 hours.


Saliva testing for drugs is administered to detect the presence of parent drugs. It’s less invasive than the urine test and less expensive than the blood test, however, its accuracy can be questionable if not done right. For instance, very little amounts of THC from marijuana or nicotine from tobacco is released into saliva. So, the detection window for the drugs is very small i.e. within just a few hours of use. However, some drugs enter oral fluid through diffusion from the bloodstream and can be detectable for a little longer. The ease of use and low cost are the key factors helping saliva test gain popularity.

Hair Follicle

Mostly is currently used for research purposes, hair follicle testing is very hard to beat but can be the least accurate approach for several reasons. The test tries to detect the presence of drug metabolites diffused from the bloodstream into the follicle. The hair test can offer data like no other, such as detecting drug as well as patterns of use. For example, if you used a drug, then abstained for a certain amount of time, and then used it again, the test will reveal all the data.

However, contamination from the surroundings is the major issue for hair testing. Even the smallest amount of a powder or smoke can get stuck into hair and could result in a false-positive test. While some renowned laboratories try to dismiss this claim but many experts believe that as compared to white hair, dark hair is a true magnet for contaminants making Asians, Africans, and Latinos more prone to false-positive results.

What is the most common type of drug test?

The most common type of drug test is a urine analysis. Of 55 million drug tests that were administered in 2015, 90 percent of them were urine analyses. A urine analysis is much cheaper than other tests and tends to have a longer detection time than if the test were conducted with blood or saliva samples.

Accuracy and Reliability of Drug Tests

Drug testing can be accurate if done properly, but can be beaten very easily and the results can be extremely misleading. The accuracy depends on how strictly the collection was done, if the collection was done inside the detection window of the drug, and whether it was random drug testing or the subject had prior knowledge of the testing.

The results of drug testing depend on how strictly the specimen was collected. For instance, when urine is collected, its temperature should be between 96 and 99 degrees. Otherwise, the subject might have contaminated their urine and the results might not be correct.

Secondly, it’s important to remember that drugs can have different detection window depending on the test. Specimen collected too soon or too late will not offer accurate results. For example, most drugs can appear in blood stream very quickly but also leave the system shortly after the use. Likewise, oral fluid testing is more accurate during the early moments of drug use. On the other hand, drugs take a while to metabolize and appear in the urine.

Randomly choosing subjects and not giving them knowledge of the test in advance doesn’t leave them time to abstain from the drug or use any tricks to beat the test.

Applications of Drug Testing

So what are the major applications of drug testing? Although drug testing is on a decline in the States, because employers have started to realize that there is little benefit for a lot of hassle. The government, as well as drug-test industry, promised the organizations that proper drug screening will ensure safety and will enhance productivity, but this really hasn’t happened. The impact can be seen in the rate of testing dropping down from 81% in 1996 to 62% in 2004. The biggest drug tester in the US is the federal government itself, subjecting 400,000 employees. However, there are several other scenarios where the application of drug testing can occur:

  • Drug testing by employers to detect the use of illicit drugs
  • Screening of athletes and sportsmen to detect any illicit performance enhancing drugs
  • Testing by police officer, for instance, testing for illicit substances in people who seem to be DUI
  • Insurance companies doing drug testing before they let an individual purchase a plan
  • Testing as a result of court order, usually in cases of child custody or after allegations of date rape drug abuse
  • Testing by a health professional to figure out causes of a disease the individual is suffering from
  • Drug test to monitor a person who is abstinent and has joined a support program

Screening before an individual undergoes orthopedic, plastic surgery, spinal fusion, wound revision, organ transplantation or pulmonary therapy.

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Drug Tests 101 – What Everyone Should Know About Screening

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Comments 45

  • Is a saliva test very accurate, especially for BEZODIAZEPINES!?

  • A failed positive how likely is that when I know I’m not doing phetnyl

    • Do you take suboxone? I just tested positive for oxy. Upon research I learned naloxone can cause false results I take no other drug! Except subs

      • Will suboxin show up in Irvine tomorrow morning if I took 8 mg strip at 7 tonight I need it to for probation it’s mandatory I take it so I need it to show up

    • If you go to a clinic that does not follow the strict protocol a false positive can happen. I have done drug screens for a major medical facility for 10 years, here are the steps in order and should not be deviated from.
      Fill out paperwork COMPLETELY, with the exception of signing your name or initialling the stickers that will go across the top of the tubes once they are locked so when they arrive at the testing lab they will be able to tell if it was tampered with. Only sign the form and initial the labels after the urine has been dispensed into the tubes.
      All water to the restroom should be off (sink and toilet). Toilet water should be dyed blue, all belongings stay outside of restroom unless locked in a cabinet and key held by staff. Patient should pick their own specimen cup that should be sealed with manufacturer seal. Patient has one minute to produce a sample, you need 15cc for a regular test and 30cc for a DOT test. You may wipe and dispose of the paper in the toilet but DO NOT FLUSH. Once you are finished with your collection you can open the door (preferably with a paper towel) and give the specimen to the staff working with you for the drug screen. NEVER GIVE IT TO ANYONE ELSE, THAT BREAKS THE CHAIN OF CUSTODY AND IF IT DOES GET MIXED UP YOU HAVE NO IDEA WHO DID IT. The person collecting your specimen should turn the water back on so you can wash your hands and gather your belongings and the staff should also flush the toilet. The person collecting your specimen then needs to have you sign the paperwork and stickers and give you a copy of it. But before that the urine is poured into either one of the locking transport tubes and labeled with your information and your initials for a single test or two tubes for a DOT test. Once all containers are full up to at least 15cc each then the tube(s) are placed in a small plastic bag with the word BIOHAZARD on it, along with the completed, signed, dated and initialed form in a separate sealed place in the bag with your name showing out and the bag placed in the locked box of what ever drug testing company that they are using.
      If these steps are not followed exactly your drug test was not performed according to laws mandating the collection and chain of custody laws for any type of drug screen. Hope this helps.

      • If there’s not 15 cc of urine, can you have a false positive?

      • So i was screened at my dr app and it showed negative for all the meds I take. I insisted it was wrong so they sent it off to a lab well guess what results showed i take all my meds! Dr said she ordered wrong test and thats why results were wrong? How can that be?

      • Does Codeine And hydrocodone show up as the same thing in drug test

  • I had a test say I had Suboxone in my system.and I was pregnant I demanded it be re tested because the paper said the keep urine for around 30 days…read your paperwork because I knew I didn’t put anything into my.body and here it was a cross contamination whatever that meant…it was a lab mistake.

  • Did random urine drug test at pain management clinic and my test came out positive for a drug called fentanyl even though I didn’t take any of that sort. My doctor knows I sometimes use marijuana for my chronic pain and suggested that maybe the one I used may have been laced with that drug….very scary. We did another test to make sure it wasn’t just a false positive so just waiting now. My question now is will that second test be able to identify if it did in fact came from the marijuana I used?? I’ve also been trying herbal stuff I got online so not sure if that’s the culprit too.

    • I dont know about your test question but i live in Baltimore and ppl are putting fentanyl in everything on the street from weed to pills to cocaine not just heroin like mant ppl think dumb mfers are putting it in everything i guess hoping ppl will get hooked and buy more im so happy China is passing laws to ban fentanyl production

    • I got kicked out of pain management for a bad accurate online review. Then your’s let’s you smoke the occasional joint . Sign me up! I’ve had two brain surgeries two spine surgeries and no cure for what I have along with daily seizures and I take 0 pain meds other than Advil !

  • i am curious about the metabolite cutoffs, I am prescribed xanax 2 mg daily as needed. I took a drug test the following morning and I am pretty sure I had taken 2 mg the night beofr as I was upset (another story). My level on my test is 413 for Alphahydroxyalprazolam (the metabolite of xanax) it’s all I take so I am just wondering if that is normal?

  • I have to see PO on Monday
    It’s Sat and I have had 4 shots of Tequila.
    Plus drank 3 beers Friday night.
    Been drinking tons of water
    Will I pass Drug test?

  • What about I have a drug screening in less than a week for epiditimitis in my testicle ,it had trace of blood before ,the concern is my gall bladder as well,point is ,the doctor won’t remove my testicle or look into my Go adder if I have any amphetemines or stimulants in my urine.how many days do I have to flush these metalobites out and still get an accurate blood count .

  • How’s about how long do I have to flush speed out of my urine for a hospital u.a. but still keep my urine intact to get a proper blood count per.

  • Question: can you pass a hair drug test yet at same time fail urine drug test?

  • I have been on morphine sulfate time release 60 mg a twice a day and morphine sulfate 30 mg 4 times a day break through for almost 14 years I recently took a drug screen at my new pain doctor and it came back positive for 16 in MA not 16 scuse me came back for 6 p.m. a.m. he told me that it was positive for heroin that that’s what that meant I’ve never take heroin or street drugs in my life ever I’m 64 years old why would that come back like that I’m told that morphine can come back a false positive sometimes but I’ve never had this happen can you please explain to me why this test has come back positive and this past Friday I had my family doctor retest me I had a blood test and urine tests done I want to get my name cleared I am been so very upset over this thank you for your

    • These drug tests can be very wrong. I went to a methadone clinic for 5 years and after getting my first 2 take home they said you have meth in your system which I had not used but it can come up from a med I take and they don’t believe you even when the prescriber told them. After I had continual clean urine and 5 take homes,the max for someone on benzos and methadone. I ended up never losing my bottles and at 5 1/2 yrs they said they were taking my bottles bc there was nothing in my urine!! How can that be when twice a week I dosed in front of them. I walked out and went on subs. Urine tests are bulls**t, it’s hit or miss!!

      • What state do you live in? I’m in Indiana and my clinic said it is illegal to prescribe methadone and benzos together? I’m pissed because I have major panic attacks and anxiety along with agoraphobia. I had to get off my meds to go to the clinic, so no I’m worse off than I was before. I feel like I live in a constant hell.

        • Jane!! Dude! Don’t proceed! Those stupid people are going to kill you or cause you to have post acute withdrawal syndrome!
          Do they have suboxone or a vivatrol shot that’s legal in Indiana?
          How long have you been on benzos? Its more crucial the length of time you’ve been taking them as vs. how much you were taking, in regards to withdrawals.
          Look up Dr. Heather Ashton on YouTube! This is truly the only safe way to get off benzos if you’ve been on them longer than 3-6years, depending on the use pattern & the person’s metabolism & emotional habits.
          Please watch out for yourself! The State doesn’t give 1 sh*t about any drug user!
          i wish you & anyone else trying to quit opiates or God forbid, benzodiazapenes, the best & send you blessings & good fortune from the bottom of my black heart.

    • This is not going to be any good for you probably, I just wonder are you using morphine or cancer or 4 spinal problems just a question I have because I’m also on morphine but I cannot get my doctor to prescribe me the right amount to help me with the pain so I can suffer is it going to end that soon if it doesn’t start so if you could tell me who your doctor is I’d be more than glad to see him

  • What year did the DOT regulation come out to start pre-employment drug testing?

  • Does a urine test specify the presence of both oxycodone and hydrocodone, or will it just specify narcotics, or opioids are in my system. I am prescribed oxycodone, but on Friday I was out of town and didn’t have my medication and a friend gave me a hydrocodone and I have a drug test Monday for pain management. Will the urine test show the hydrocodone in my system as well as the oxycodone that I am prescribed?

  • Does gabapentin show up in urine tests?

    • It’s not a narcotic so it shouldn’t show up. I think you’ll be ok.

    • Yes gabapentin will show up on a drug screen IF they test for it. I went to a suboxone clinic and they test for them now, they didn’t before but do now. So I guess it all depends on what they order the lab to test for. Now that gabapentin is considered a scheduled drug and a drug of abuse im sure that people are going to start testing for it more often.

  • I took a drug screen but told them I took a hydrocodone so I should be coming up positive for opiate. Really I did some heroin but normally when the results come back it says positive for opiate. My question is can a drug screen specify that I took heroin or with it only come back for opiate?

  • I drug test every two weeks and I used heroin for one week and I did meth for one day if I have five days until drug test will I come out positive or negative any advice from anyone thank you

  • I would like to know where I can get and see the actual results from my drug screen. I need to see it for myself.

  • my husband goes to pain managment for broken neck and back and every drug test they took on him keeps coming back neg why we dont understand it why it keeps coming back neg although he is a diabetic and drinks like 3 gallons of water a day and other fluids like tea and soda could that be the reason he is coming back neg all the time pluss he has keyoacidoses his A1c is high sugar never under 300

  • Yesterday I took a drug test for pre employment & when I gave the lady the urine sample she asked me did I take any medication & she was sticking the stripes in it.. I told her no & then she told me I can get my belongings out the cabinet & I left.. why would she ask me that? Do they just ask random questions like that

  • Ok, i wanted to try & help anyone taking a saliva test. This seems to have worked for my roommate. This might only be applicable to the test Amazon gives for their employment screen. And obviously, so far, only applies to my friend.
    But this is what we did: i made a ‘solution’ (super chunky) of activated charcoal & distilled water. About 10-15grams (so almost a level TBSP) of the a.c. (i used a fine ground powder. If you have a bottle of tablets, i would take around #2-4 250mg tablets & thoroughly smash into a fine powder & just add to a much smaller amount of distilled water than i used, like approximately a shotglass-full. Mix as well as you can). i was making a much larger quantity (90mls/3 oz.s). i put this into a plastic bottle. i’ll come back to this.
    Then, i sifted approximately 2tsp.s (10 gms) of potassium bitartrate (aka Cream of Tartar) into about 45ml.s/1.5 oz.s distilled water, & put this into another plastic bottle, & shook it like mad.
    Ok, so you can totally substitute citric acid for the cream of tartar. Or even ascorbic acid, or even vinegar if you have nothing else. Or lemon or lime juice. Sour & acid is what you want.
    In addition to the normal bottle caps, i brought a sprayhead that fit from another bottle & a cone-shaped nozzle-type cap that fit (if you had a nasal squeezie bottle that would also work).
    Also, i gave her #2 0.2mg clonidines to swallow a half hour before & an albuterol inhaler to hit when she got there. Both of these drugs supposedly cause extra salivation. If you don’t have either or one, don’t sweat it. It can totally still be done.
    Then, before leaving the house (30minutes before the test),
    she brushed her teeth & mouth really well & rinsed using biotine dry mouth mouthwash, but any would work, probably.
    We left, bringing everything with us. Its a 30minute drive.
    At the 10minute mark before arriving, i had her shake the charcoal solution, take a swig & swish for like a minute. Then spit it in another bottle. Second, i had her shake it again, take another of the same, & gargle with it, then spit it out. Lastly, i had her switch the cap for the nozzle, shake it once more & squeeze a scosh up each nostril. That was rough..
    Next, i had her repeat the entire process with the acidic solution, check her nose before going in & right before getting out the car, i had her switch that cap for the spray cap & take the bottle of the clear acidic solution in with her, to spray discreetly straight behind her bottom back molars & under her tongue once inside waiting for her name to be called.
    Also, like i said, she hit the inhaler twice before going back to take the test. This will probably work for a full 15-20minutes after that last spritz, before your mouth & saliva ‘re-normalize’. With all these extra steps, maybe a little longer.
    i know this seems like overkill, & it was, but, she shoots up heroin every day (which has a suuuper short half-life, which is great), but also, smokes meth all & every day, all day & nite long. She weighs about 160, & is 5’7 or 5’8. She’s been a chronic daily user for 20 yrs, & is 38 now.
    The most important parts to remember is first to clean your mouth, tongue, throat, (& sinuses, if you’re paranoid like me), & second, to do whatever you have to in order to make yourself salivate like a basset hound.
    Yeah, i wanted her to get a job.
    Anyways, it worked.

    • All I can say is I wouldn’t want her working for me if she’s that drugged up. Hope she doesn’t get a job in the medical field or working with children or anything that requires any responsibility!! Maybe she should get help getting off all those drugs instead.

  • If someone used meth and cocaine yesterday.. how can she passed a drug test tomorrow? Less than 48 hours since she used drugs..

  • I was wondering if anyone had heard of someone being called back in to provide another sample for a preemployment drug screen. I provided a urine sample a few days ago and have yet to receive my results. I want to make sure I’m not going to be called in again before I smoke.

  • I took a drug test at my Drs. because I take hydrocodone and the law requires I take them at periodically.
    My drug tests have always been good. Then two test in a row showed no sign of the hydrocodone
    In my system.
    I take several different prescriptions. I started taking a new one, phentermine. Some of the other prescriptions I take are Omeprazole, Xanax, flexeril, gabapentin etc..
    Is there any one or combination of prescriptions that can cause a false negative result for hydrocodone? I had taken 2 300/7.25 the day before my drug test. I don’t take them if I don’t need them on a day to day basis.

  • The. Codeine and hydrocodone Show up the same thing in drug test

  • Will fentynal show up the same as vicodin on drug test..this is for probation

  • I took a UA about 3 weeks ago, I got a email today from my employer that they can do UA and blood. Well when I did my UA on the paper it only had UA marked but they took blood to see if my TB was good. How long is the blood they took good to test if they Do test from the sample given for my TB because at the time I didn’t consent a blood test.

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