What kind of drugs they looking for?

1. Cannabinoids (marijuana, hashish - tests for metabolite THCCOOH)
2. Cocaine (cocaine, benzoylecognine, cocaethylene)- tests for cocaine metabolite)
3. Amphetamines (amphetamine, methamphetamine)
4. Opiates (heroin, opium, codeine, morphine, 6-MAM)
5. Phencyclidine (PCP)
6. Methadone (MTD)
7. Barbiturates (BAR)
8. Benzodiazepines (BZO)
9. Tricyclic antidepressants (TCA)
10. Methylenedioxymethamphetamine (MDMA or ecstasy)

Additional tests include synthetic pain killers such as Oxycodone (Oxycontin, Percocet), Oxymorphone, Hydrocodone (Vicodin), Hydromorphone, benzodiazepines (Valium, Xanax, Klonopin, Restoril) and barbiturates in other drug panels (a "panel" is a predetermined list of tests to run). The confirmation test (usually GC/MS, or LC/MS/MS) can tell the difference between chemically similar drugs such as methamphetamine and methylenedioxymethamphetamine (MDMA or ecstasy), and in the absence of detectable amounts of methamphetamine in the sample, the lab will either report the sample as negative or report it as positive for MDMA. What the lab reports to the client depends upon whether MDMA was included in the panel as something to be tested for.

Gamma-hydroxy-butyrate (GHB) was not routinely tested for in the early 1990s, but due to increasing use, some laboratories have added it as an optional test. GHB is rare in pre-employment screening, but is commonly checked for in suspected cases of drug overdose, date rape, and post-mortem toxicology tests. Ketamine (Special K) may or may not be tested for, depending upon the preferences of the entity paying for the test, though testing for it is uncommon. In general, the greater the number of drugs targeted, the higher the cost of the test, which means that many employers only target the NIDA 5 for financial reasons.

Other drugs, such as meperidine (Demerol), fentanyl, propoxyphene, and methadone are not commonly tested for in most pre-employment situations. These drugs are more likely to be included in tests for certain demographic groups (such as healthcare workers, drug rehab patients, etc.)

Hallucinogens other than cannabis and PCP, such as mushrooms (psilocybin), LSD, Ketamine (Ketamine) and peyote (mescaline) are rarely tested for.