Let's allude to the history of drug testing in the United States. Drug testing began in the late 1980s with the testing of certain federal employees and specified DOT regulated occupations. Drug testing guidelines are established and regulated (by the Substance Abuse and Mental Health Services Administration or SAMHSA, formerly under the direction of the National Institute on Drug Abuse or NIDA). SAMHSA / NIDA require all companies test for the presence of certain drugs professional drivers, specified safety sensitive transportation or oil and gas related occupations, and certain federal employers. These test classes were published more than twenty years ago, and they include five specific drug groups. This classification don’t account for accepted drug usage patterns. For example, the tests do not include semi-synthetic opioids (oxycodone, oxymorphone, hydrocodone, hydromorphone), and other compounds that are abused in the United States:

1. Cannabinoids (marijuana, hashish)

2. Cocaine (cocaine, benzoylecognine, cocaethylene)

3. Amphetamines (amphetamine, methamphetamine)

4. Opiates (heroin, opium, codeine, morphine)

5. Phencyclidine (PCP)

Let's call attention to the fact that many drug testing labs and on-site tests also offer a wider or "more appropriate" set of drug screens which are more reflective of current drug abuse patterns while SAMHSA /NIDA guidelines only allow labs to report quantitative results for the "NIDA-5" on their official NIDA tests. You see that these tests include Oxycodone, Oxymorphone, Hydrocodone, Hydromorphone, benzodiazepines (Valium, Xanax, Klonopin, Restoril) and barbiturates in other drug panels (a "panel" is a predetermined list of tests to run). These are synthetic pain killers. The confirmation test (usually GCMS) can show the difference between chemically similar drugs (for example methamphetamine and ecstasy), and in the absence of detectable amounts of methamphetamine in the sample, after that the lab will report the sample as negative or report it as positive for MDMA. And the lab’s report to the client depends upon whether MDMA was included in the panel as something to be tested for.

Let’s give attention to Gamma-hydroxy-butyrate (GHB). It was not tested for in the early 1990s, but some labs have added it as an optional test because of increasing use. GHB is usually tested for in suspected cases of drug overdose, date rape, and post-mortem toxicology tests. Nevertheless, GHB is rare in pre-employment screening. Some words about Ketamine (Special K). Testing for it is uncommon. It can or can’t be checked for and main reasons are preferences of the entity paying for the test. Frankly speaking, the price of the test is higher if the number of drugs tested for is greater. Due to these circumstances, many employers stick to the NIDA 5 for financial reasons.

And now let's speak in brief about some other drugs. Meperidine (Demerol), fentanyl, propoxyphene, and methadone are not commonly tested for in most pre-employment situations. But sometimes they are included in tests for healthcare workers, drug rehab patients and etc. As for hallucinogens other than cannabis and PCP (we mean mushrooms (psilocybin), LSD, and peyote (mescaline)) they are tested for very seldom.

The most common way to test for drugs is urine drug testing. But also the hair, saliva, blood or perspiration may be drug tested because there are a lot of different drug testing methods. If you want to understand the main principles behind drug testing technology, we should approach the way in which the body deals with drugs. Pay attention that all drugs undergo a series of bio-chemical reactions in the body. The active compound is released with the help of these reactions and then the drug is gradually degraded into slightly different structures which are also called metabolites. Then they are excreted from the body with the help of different ways. It’s the fact that the main excretory route for drugs and their metabolites is urine.

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