Millions of people around the world abuse drugs. If asked, many of them would not be honest about their consumption. For this reason, tests are commonly administered to determine whether or not a person has used substances such as cocaine or marijuana. Drug test kits are the tools used for this task.
There are several types of drug test kits. One of the biggest differences between them is they are designed to detect different substances. There are testing kits that can be used to detect a certain drug and there are testing kits that can identify multiple drugs. A five panel drug test, for example, is generally used to detect amphetamines, opiates, cocaine, cannabinoids, and phencyclidine (PCP). A 10 panel drug testing kit, which is more thorough, has the ability to detect the aforementioned substances and others, such as barbiturates, methamphetamines, and methadone.
Another difference in drug test kits is the method that is used. Saliva, urine, and hair are examples of bodily materials that can be used for testing. Urine tends to be the most common, however, and it is often the cheapest material to examine.
Drug test kits have a number of limitations. One of them is that although these tools can detect the presence of drugs, they cannot generally determine how long ago the drugs were taken. Also, two people can take the same drugs on the same day and they can also take the same type of drug test. The results may be positive for one and negative for the other.
The reason for this is that numerous metabolic factors determine how fast a person’s body eliminates the traces of the substances she has used. A drug test does not generally determine whether or not a person has ever taken drugs. The test only determines if the substances are present in the body at the time of the test.
The popularity of drug test kits significantly increased their availability. At one time it was rare to find a person who had a drug test performed outside of a medical facility or laboratory. Now, many businesses purchase equipment and administer pre-employment drug screening on site. Testing kits are also widely available on the Internet and in retail stores such as pharmacies and superstores. People sometimes purchase them to see what the results are likely to be for official tests, and parents often use them to determine whether or not their children are using drugs.
Hair drug test is a widely-used drug testing methods nowadays for its ability to provide accurate results. Law enforcement officials, employers, parents, and other individual parties are among those who use hair drug testing kits to determine a person’s drug history or recent drug use. This hair drug screening is not only reliable but also ensures that even a small amount of a drug will be detected.
These hair drug testing kits provide an approximate 90-day drug usage history. Using a hair sample of approximately 120+ strands of hair cut at the scalp, hair analysis evaluates the amount of drug metabolites embedded inside the hair shaft. For those individuals with no hair available on the scalp, body hair also acceptable. These hair follicle drug test kits are designed with high quality that no amount of shampoo, bleaches, and external contaminants can affect the results.
Hair testing generally uses 1-1/2 inches of hair, representing about 3 months’ growth (head hair normally grows at about 1/2 inch per month). It is generally accepted that in order to test positive, the drug in question must have been used 3 times or more within the window of the test. After a drug is used, it takes about 7-10 days for the hair containing the drug to grow out of the scalp enough to be cut. Therefore, the hair test will not include drugs used in the week prior to the test. The drug remains in the hair, growing out much the same as "dark roots". Eventually that hair containing the drug is cut off with normal haircuts.
There are some prescriptions that contain the same drugs that are commonly found "on the street". There is no easy way to distinguish between the two forms of the drug. However, the problem is not as big as it would seem.
There are no prescriptions for PCP or cocaine. It is extremely rare to find cocaine used in a medical setting, although it happens occasionally, usually to control bleeding from the eye or nose. If used, it will be well documented in the person’s medical file. Such use would cause the urine to test positive for cocaine metabolite for a few days, but would not be sufficient to cause a positive hair test.
Heroin is rarely prescribed in the United States, but again would be well documented. It appears that poppy seeds do not interfere in hair testing. Other prescribed opiates may occasionally cause a positive screen, but are sorted out in a confirmation test.
There are some prescription diet pills that contain either amphetamine or methamphetamine, as well as a drug for Parkinson’s Disease that is a form of methamphetamine. Some doctors prescribe amphetamines for ADHD. Ecstasy is included in the amphetamine class of drugs, and is identified at confirmation.
Because there are substances that interfere with screening, causing "false" positive results on screening, the positive screen must be confirmed. The accepted, state-of-the-art method is called GC/MS, gas chromatography/mass spectrometry. Each drug peak comes off the GC at a specific time (retention time), and with specific ion ratios, allowing it to be separated or distinguished from similar substances. To be called positive, the peak in the sample must match a known pure standard of the drug in question in both retention time and ion ratios. In addition, the presence of metabolites may be checked. For instance, amphetamine is the major metabolite (what the body turns it into) of methamphetamine. So, If there’s been methamphetamine use, the hair should contain the methamphetamine AND amphetamine. Likewise cocaine. Cocaine users will show positive for cocaine AND the metabolite, benzoylecgonine. Finding the parent drug without the metabolite for these drugs is suspicious, and needs to be investigated.