A drug test is the technical analysis of a biological specimen (sweat, urine, blood, or oral fluid) for the presence of specified parent drugs or metabolites. Its purpose is to determine whether an individual has used alcohol or other illegal drugs. It can also be performed to detect a specific substance in urine, oral fluid, hair, and saliva.
Oral fluid testing
Oral fluid drug testing is a laboratory-based test that can identify drugs present in oral fluids. The test is based on two steps: the first involves a substance that reacts with a specific enzyme that competes with the target drug. The second step uses a solid surface to detect the presence of the drug, resulting in a color change and chemical signal.
Oral fluid testing has several advantages over urine or blood testing. It is less invasive and can be done both prior to and during employment. In addition to being less invasive, oral fluid tests provide fast results. They are also available in panels that cover only federally covered drugs. Additionally, oral fluid testing is available as part of alcohol screening tests.
Hair testing
Hair I Drug Screen testing is an effective way to detect illegal drugs in the body. The procedure uses a small sample of hair and can detect traces of marijuana, cocaine, amphetamines, methamphetamines, PCP, opioids, and other drugs. It is pioneered by DISA vendor partners and is considered to be cheat-proof.
A hair sample is collected from the subject and delivered to a certified laboratory. For most tests, the result is returned within two to three days. For more complex tests, the time frame may be longer. Depending on the drug being tested, confirmation testing may be required. For this reason, the process of hair testing may take a few days more.
Although the detection window for hair testing is smaller than that for urine, it is appealing to those who use drugs intermittently and less frequently. The procedure is easy and does not pose a biohazard. It also does not require a special storage facility and is less intrusive than collecting urine specimens. In fact, hair testing is becoming a popular outcome measure in some clinical trials.
GC-MS testing
GC-MS is a powerful analytical tool for drug screening. This new platform is able to detect a wide variety of drugs. In fact, it has helped clinicians in several complex toxicology cases. For example, in a recent case study, the GC-MS platform helped identify the drugs that were causing a patient’s altered mental state. She had shared a room with a patient with a similar name but had been prescribed drugs that were not used by her roommate.
GC-MS is a highly sophisticated drug test and has been dubbed the “gold standard” in the industry. However, it is a relatively expensive test and most laboratories prefer to use it only for confirmatory tests. It is still considered a high-level method of testing, though, and is used by many industries that are regulated by the Department of Transportation.
GC-MS
In a study of GC-MS performance, AMDIS improved the rate of reported drugs over baseline using five different configurations. This combination of an in-house library and a new GC-MS instrument produced a statistically significant increase in reported drugs per patient. These results are presented in table 1.
This method is highly sensitive and accurate, identifying over 100 drug substances and metabolites in urine. The results are presented in a report that includes chromatographic and immunoassay screening results and a list of the drugs detected. However, it is important to note that the chromatographic properties of some commonly encountered drugs are poor and they will therefore produce a positive immunoassay screening result. For example, the most commonly used drugs in the benzodiazepine class will result in a presumptive positive result, even if they are toxic.
The new platform also employs a highly sensitive GC-MS method. This method makes use of PTV injection technology for sample injection and a public data analysis package (AMDIS). GC-MS is capable of detecting a wide range of drugs and is able to report them in a single sample. In addition, the new quadrupole mass analyzer offers improved ion transmission.
GC-MS test
A GC-MS test for an eye drug screen is useful for detecting the presence of certain drugs in urine. This test is typically performed as part of a comprehensive drug screen or in conjunction with a preliminary drug screen. It can be used to check for a wide range of drugs.
GC-MS tests use a combination of gas chromatography and liquid chromatography with tandem mass spectrometry. This process allows for a more detailed analysis of drugs and can identify the toxicants involved. The results of the analysis are compared to the patient’s medical records.
Data were obtained from a subset of patient samples containing a wide range of drugs. The data were analyzed using a new in-house library and a reference GC-MS instrument. The combination of these two methods produced a significantly higher number of reported drugs for each patient.
