What is drug screening? How does it work?

Screening tests for the use of drugs is becoming more and more common every day particularly since drug abuse and substance abuse are so common. Workplace drug testing is required for many types of employment. You may be asked to do a drug screening test as a pre-employment requirement or for continuing employment especially in high-risk jobs to the public such as airline pilots. The United States Military has a strong drug policy which requires drug screening to join or to continue as a member of the Military. Since drug screening is becoming so popular, you should learn all that you can about it, such as what is a drug screening test, how does it work, what is it used for and what do drug tests detect.

What is a drug screening test and how does it differ from drug testing? A drug screening test is a fairly simple method to determine which of a number of possible drugs you might have been using. The test is usually done on a urine sample but in the case of alcohol testing it may be done on a breath sample using a “breathalyzer.” Drug screening results are usually available in minutes and commonly test whether certain drugs have been used or not, but they don’t usually tell exactly what level of drugs there are in the sample. Drug screening tests of blood, hair, and sweat must usually be sent out to a drug testing facility or laboratory and results are not usually available for a period of at least 24-48 hours.

Drug test typing. What drugs do tests detect?

Drug screening tests can show one of three results. A negative test indicates no drug use within the period of time the drug test covers. A positive test indicates drug use but usually will not tell how much of the drug was used. A positive drug test will usually result in a second more sophisticated test method usually performed at a drug testing facility, called a gas chromatography/mass spectroscopy (GC/MS) test which can detect exactly what substances have been used and at what level. An indeterminate test or an unacceptable sample will almost always result in a repeat test.

Gas chromatography/Mass Spectroscopy (GC/MS) can detect 17 different drugs in hair samples, including amphetamine, methamphetamine, methylenedioxymethamphetamine, 3, 4-methylenedioxymethamphetamine, methelenedioxyethylamphetamine,  methylphenidate, cocaine, benzoylecgonine, morphine, codeine, heroin, 6-monoacteylmorphine, methadone, 2-ethylidene-1, 5-dimethyl-3,3-diphenyl pyrrolidine (EDDP), Delta-9-tetrahydrocannabinol (THC), nicotine and cotinine in human hair. GC/MS can also detect the date rape drug, GHB or Gamma-hydroxybutyric acid.

The hair follicle drug test is useful in detecting a history or prior drug use as long as 90 days before the test and uses the GC/MS method for detection of drugs present in hair samples. The hair follicle drug test timeline thus gives can detect a long history of drug use and is very specific. The hair preparation method includes a three-step wash procedure followed by a hair pulverization and extraction procedure with disposable metal balls. The developed liquid chromatography-tandem mass spectrometry method uses a single injection to detect and confirm all 17 drugs of abuse including THC within 4-8 minutes.

Why then might you need to take a screening drug test? Drug-free workplace environments have caused many corporations and even smaller employers to require pre-employment drug tests as a standard policy for initial employment. Workplace drug testing is also commonly required for continuing employment. Staffing agencies which help employers to find qualified employees almost always require a drug screen before accepting potential employees into their programs. The Department of Transportation (DOT) requires drug testing for many employees who work in the airline, railroad, trucking, maritime, pipeline, and bus industries. DOT mandates and specifies exactly what tests need to be done to meet their requirements for employment within these industries. Athletes, particularly those who may compete in international athletic competitions may need drug tests to show that they comply with the World Anti-Doping Code prohibited list which includes drugs such as anabolic steroids, erythropoietin, diuretics, and recombinant human growth hormone, among many others.

Another source of the requirement for drug tests is the legal system. Drug screening may be required for DUI, child custody, divorce, and probation situations. The investigation of accidents either in the workplace or outside such as related to traffic accidents are also situations in which drug testing may be necessary. Drug testing is also used in professional athletes regarding anabolic steroids and other proscribed drug usage. Physicians and health centers, particularly those dealing with chronic pain in which opiate usage is common, are also sources of drug screening. Rehabilitation centers for the treatment of drug abuse or substance abuse require testing to ensure that their patients are not continuing to use proscribed drugs. Investigation of crimes of all kinds, including date rape using the so-called “date rape drug” which is GHB or Gamma-hydroxybutyric acid and questions of heavy metal poisoning and the use of Club Drugs may also be situations in which drug screening or testing is required.

Drug abuse is a major problem for societies throughout the world and the World Health Organization (WHO) defines drug abuse as the harmful or hazardous use of psychoactive substances, including alcohol and illicit drugs. Psychoactive substance use can lead to dependence syndrome – a cluster of behavioral, cognitive, and physiological phenomena that develop after repeated substance use and that typically include a strong desire to take the drug, difficulties in controlling its use, persisting in its use despite harmful consequences, a higher priority given to drug use than to other activities and obligations, increased tolerance, and sometimes a physical withdrawal state. Because drug abuse is so widespread in society, testing for drugs has become a very important way to get a handle on this serious problem in all walks of modern life.

As you can see by now, in today’s world it is very likely that sooner or later you will be requested to so either a drug screening or drug testing. What then is the difference between a drug screening and a drug test. A drug screening is a way of rapidly testing for a whole range of drugs and substances in a qualitative way, that is, have you used certain drugs or not. Drug testing is quantitative testing to determine exactly what drug you have in your system and how much of it.

Drug screening offers a fast and inexpensive way of getting a general idea of drug usage, particularly for employers. The screening test is so-called immunoassays because they use the reaction of drugs with your body’s immune system to produce antigen-antibody complexes which are what the tests actually test for. Screening tests often do not test for drugs specifically but for their immune signatures in your body.  The tests usually involve your urine specimen causing a color change on a test strip which is calibrated according to specific guidelines for drug usage. For instance, the generally accepted threshold for a positive test of THC is above 50 nanograms per milliliter (ng/ml) but for the military, the threshold is only 15 ng/ml.

These screening tests are cost-effective for employers and give almost immediate results, but they are prone to false positives drug tests and may miss certain drugs such as opiates like heroin, oxycodone, methadone, codeine, or morphine. False positive tests for opiates may be caused if you have eaten poppy seeds or used an over-the-counter cough medicine containing Dextromethorphan! Ibuprofen a commonly used non-steroidal over-the-counter pain medication can cause a false positive test for marijuana and ephedrine commonly present in over-the-counter nasal decongestant sprays can cause a false positive test for amphetamines.

If a drug screening test is positive or equivocal, a second specific drug test using the GC/MS test will usually be required on the same sample that gave the original screening test result or on another sample collected at a later time. The GC/MS test is very specific for individual drugs and, as mentioned, can test for as many as 17 different drugs and drug metabolites. Because the GC/MS test is very specific it can eliminate false positive drug tests and evaluate very precisely the drugs being tested for. The usual urine screening test for marijuana the EMIT test does not actually test for THC, the psychoactive component of marijuana but tests instead for THC-COOH which is a metabolite of THC and is more a test of prior use of marijuana rather than a test of current use. The GC/MS test, however, tests directly for THC itself and so is a measure of current marijuana use. The GC/MS test is more expensive than simple screening tests and it takes longer to get results, typically at least 24-48 hours but the GC/MS test rarely shows false positives. Both tests may give false negative tests, especially the screening tests when drug usage occurs on the same day as the test.

The most commonly used drug screening test used by employers and government agencies is the 5-panel drug test which screens for the most common drugs of abuse including cocaine, methamphetamines, cannabis, opioids and PCP or phencyclidine. Some 5-panel tests may also test for alcohol in addition, but alcohol stays in the blood for less than 24 hours after consumption. The screening test also tests for validity including the temperature of the specimen and normal constituents such as creatine, pH and nitrites.

Less commonly used by more comprehensive is the 10-panel drug test. In addition to the five tests used in the 5-panel test, the 10-panel test usually includes testing for oxycodone, methadone, benzodiazepines such as Valium or Xanax, barbiturates such as Amital, Fiorinal, Nembutal, and MDMA or Ecstasy. And even beyond the 10-panel test are companies that offer as many as 52 different tests of urine, blood, and hair to include drugs such as fentanyl, acetyl fentanyl, gabapentin, ketamine, tramadol, nicotine, phenytoin, tricyclic antidepressants, and valproic acid.

With this information in mind, how should you prepare for a drug test? The answer depends upon how much advance notice you have of the test and what kind of test you have to take. If you have plenty of time the best approach is to stop using drugs which may show up in the urine drug test such as marijuana which will allow your body’s natural detoxification processes to begin to eliminate the drug or drugs from your system.

Exactly how much time you have depends on several factors such as what drug you are using, what dose of the drug you take and for how often you take it as well as your age, sex, body weight, and in the case of some drugs, your ethnicity. Thus, two people using the same drug can have very different times for the drug to disappear from their urine.  In the case of the benzodiazepine Xanax, people who are obese, over the age of 64, who have liver problems and are either Asian or white will retain the drug in their systems for longer than the average predicted time. For marijuana, people with a high body fat content and slow metabolism who are not very physically active will store the cannabis metabolite THC-COOH in fat tissue and detoxify it slowly. On the other hand, people with low body fat content and a high metabolic rate who exercise vigorously will detoxify marijuana metabolic products like THC-COOH which is the basis for the marijuana drug test, much more rapidly. Table 1 gives some general guidelines for how many days some commonly used drugs may stay in your urine.

The type of drug test you will take is another factor in determining how long certain drugs or drug metabolites will be detected. Blood tests tend to show very recent drug use while hair tests can show drug use up to 90 days before the actual test. Urine tests vary greatly depending on what drug is involved. In general drugs such as alcohol are gone in 24 hours whereas drugs like cocaine or opiates are detectable for 2-4 days, but marijuana metabolites may be detectable for many days, weeks or even months.

How to pass a drug test home remedies?

For regular, heavy users of marijuana, THC-COOH may be detectable above allowable levels for several months after prolonged abstinence. In considering abstinence as a method to deal with an approaching drug test you should also take- into- account possible withdrawal symptoms from marijuana but also from drugs such as opiates or alcohol. Withdrawal symptoms may be severe including the phenomenon called Delirium Tremens from alcohol withdrawal which can result in paranoia, delusions, convulsions or even death. Withdrawal symptoms from other drugs may include flu-like symptoms, anxiety, depression, restlessness, and suicidal thoughts. If you are a regular user of marijuana or other addicting drugs, you should consult a qualified physician or substance abuse treatment program before starting a “cold turkey” abstinence program on your own. The Substance Abuse and Mental Health Services Administration (SAMHSA) is a good source of information about drug withdrawal and it’s symptoms and can refer you to a qualified treatment program if necessary.

Suppose that you have an upcoming drug test and you are concerned about THC. What can you do to pass a drug test for THC in addition to abstinence? What is the best way to pass a drug test on short notice? You can use one or more of several things which might be considered home remedies, in addition to abstinence, including drinking large amounts of fluids, especially those containing electrolytes such as Gatorade or Pedialyte which will help flush THC-COOH from your system. Drinking large amounts of plain water over a prolonged period can lead to a condition called water intoxication which can cause serious neurological symptoms including convulsions due to electrolyte depletion.

A host of other home remedies such as pickle juice, cranberry juice, Niacin or Vitamin B 3, Goldenseal Herbs, vinegar or acetic acid and fruit pectin a soluble type of fiber, have all been shown to either be of little or no value as home remedies.  Aspirin or Bleach which are also sometimes recommended as home remedies can have grave or even fatal consequences and therefore cannot be recommended.

Exercising vigorously will increase your metabolic rate burn fat tissue thus releasing THC-COOH to be excreted in your urine. It is recommended, however, not to exercise vigorously within 2-3 days of your test because to do so may increase the amount of THC-COOH in your test urine sample rather than decrease it. Eating a diet which is rich in high fiber vegetables will cause THC-COOH to be eliminated via feces and the colon rather than in your urine so that such an approach is helpful on the day of your test or perhaps on the day before your test. Eating a diet containing lean red meats which contain creatine will cause the breakdown product of creatine, which is creatinine, to be present in your urine sample which is one of the ways that urine specimens are tested for validity. Drinking too much and diluting your urine will cause the creatinine level to be too low and will invalidate your test. Taking B vitamins particularly Vitamins B 1, 2, 6 and 12 will help to color your urine a natural yellow to again help your sample in passing the validity test. Multi-vitamin pills are easily obtained at any drug store.

I think that you can see that most of the suggested methods for passing a THC drug test do require some time and planning but what if you have perhaps only 24 hours- notice of your test? How then to pass a drug test in 24 hours?  In that case, you might want to try a commercially available drug detox drinks or pills.  In addition to the specific components of a detox drink or pill, they all depend on the intake of large amounts of fluids to flush toxins from your system. These products all contain several essential and components to help you pass your cannabis drug test on short notice.

The main ingredients of these detox drinks or pills are electrolytes such as sodium, potassium, and chloride, and Vitamins, particularly Vitamins B 1,2,6 and 12 which help to recreate the normal yellow color of a very dilute urine specimen. They also contain creatine to ensure a normal creatinine level in your urine sample to pass the validity test. In addition, most commercially available detox drinks and pills contain a variety of herbal compounds in proprietary blends which are said to help in the detoxification process. Some detox formulations are combinations of drinks and pills which are combined into detox programs lasting from as long as 10 days or more to as little as 24 hours, the later ones to help you pass a drug test on short notice.

If you have time, a good idea is to obtain an at-home drug test that you can administer yourself so that you can approach your test with confidence that you will pass. On the other hand, if the test shows positive then, if possible, you should delay your test until your at-home test is negative. At-home drug tests are widely available and you can find good reviews at several sources. In addition, you can schedule a 10-panel drug test near you without a doctor’s prescription and with same-day walk-in service,

Table 1. The average time that drugs will continue to show up in a urine drug test from American Addiction Centers.