Urine drug testing is an essential component of monitoring patients who are receiving long-term opioid therapy, and it has been suggested for patients receiving long-term benzodiazepine or stimulant therapy. Family physicians should be familiar with the characteristics and capabilities of screening and confirmatory drug tests. Immunoassays are used for initial screening and can give false-positive and false-negative results. All results are considered presumptive until confirmatory testing is performed. False-positive results have significant implications for a patient's pain treatment plan, and false-negative results can be a missed opportunity to detect misuse. Urine drug testing is an essential component of monitoring patients who are receiving long-term opioid therapy, and it has been suggested for patients receiving long-term benzodiazepine or stimulant therapy. Family physicians should be familiar with the characteristics and capabilities of screening and confirmatory drug tests. Immunoassays are qualitative tests used for initial screening of urine samples. They can give false-positive and false-negative results, so all results are considered presumptive until confirmatory testing is performed. Immunoassays for opioids may not detect commonly prescribed semisynthetic and synthetic opioids such as methadone and fentanyl; similarly, immunoassays for benzodiazepines may not detect alprazolam or clonazepam. Immunoassays can cross-react with other medications and give false-positive results, which have important implications for a patient's pain treatment plan. False-negative results can cause missed opportunities to detect misuse. Urine samples can be adulterated with other substances to mask positive results on urine drug testing. Family physicians must be familiar with these substances, the methods to detect them, and their effects on urine drug testing.
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Specific immunoassays must be ordered for different substances; therefore, physicians should be familiar with the test used in their office and at the reference laboratory they routinely use. The typical immunoassay can detect only nonsynthetic opioids (morphine and codeine). The immunoassays used for workplace testing programs are useful for detecting illicit substances such as cannabis or cocaine, but they do not reliably detect synthetic or semisynthetic opioids (e.g., methadone, buprenorphine, oxycodone, oxymorphone, fentanyl) or help distinguish between various opioids. Therefore, many laboratories require a specific order to test for semisynthetic and synthetic opioids and other drugs such as carisoprodol (Soma). Immunoassays that test for the presence of other common prescription drugs, such as benzodiazepines, are also available. Many benzodiazepine immunoassays reliably detect nordiazepam (metabolite of diazepam [Valium]), oxazepam, and temazepam (Restoril), but not alprazolam (Xanax), lorazepam (Ativan), or clonazepam (Klonopin).10 Hence, a positive screening result must always be followed with confirmatory testing. Furthermore, if benzodiazepine use is suspected, the sample must be sent for additional testing despite a negative initial screening result.
Urine samples are sometimes contaminated deliberately by ingestion or addition of a foreign substance to prevent detection of illicit drugs. Common methods of tampering include dilution with water, addition of extraneous substances, or substitution of samples. Table 4 lists commercially available agents marketed to help disguise the presence of illicit drugs in urine samples.15,21 Many laboratories now routinely check urine creatinine levels to determine whether the sample is excessively dilute and to check for the presence of adulterants. Several commercially available point-of-care systems check for the presence of adulterants in addition to the substances being tested for.21 Although these systems can detect adulterants, they cannot determine which substances are being concealed. The practice known as shaving can also confound drug test results: a patient who is not taking the prescribed drug will add a small amount of the drug directly to the urine specimen to avoid having a negative test result. In these cases, the urine will test positive for the drug—often at a high concentration—but not for its metabolite. Such results should raise suspicion of medication nonadherence. Table 5 lists possible unexpected results from urine drug tests and potential causes.
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A drug test uses a biological sample (such as blood or urine) to detect the presence or absence of a legal or illegal drug. Drug tests are ordered and performed in a variety of settings with a variety of techniques.
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Drugs include legal substances such as alcohol and tobacco, as well as over-the-counter medications, prescription medications and illegal substances. A single drug test can’t determine the frequency and intensity of substance use and, thus, can’t distinguish casual substance use from substance use disorders.
Your body metabolizes (breaks down) various drugs at different rates, so the timeframe for detecting certain drugs in your system can be very specific and vary widely from substance to substance.
Urine drug testing (UDT) is the most common test for detecting drugs.
You may need a drug test for several reasons. The most common use of drug testing is in the workplace. Employers may require a drug screening for various reasons, including:
Another common use of drug testing is for the diagnosis, treatment and monitoring of alcohol use disorder and substance use disorder. As a tool for monitoring, drug testing can help determine treatment adherence, monitor abstinence and detect early relapse.
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You may need this testing for court-ordered treatment programs, as a term of probation or while participating in a substance use disorder treatment program.
Other uses for drug testing include:
There are several kinds of drug tests based on the biological sample they use and the types of drugs they detect.
Different types of drug tests based on the sample used include:
For more information, please visit Drug Of Abuse Tests.
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When a drug enters your body, your gastrointestinal tract absorbs and distributes it to the rest of your body. Your liver and other organs metabolize the drug (break it down). Metabolic processes cause the drug to turn into different chemicals, called metabolites. After a certain amount of time, the drug and/or its metabolites leave your body, mainly through your urine.
A drug test screens for certain drugs and/or their metabolites in a biological sample (such as urine or blood).
The metabolic processes happen at different speeds for different drugs. Because of this, each drug and its metabolites have a different timeframe in which a drug test can detect them.
For some drugs like amphetamines, the main (parent) drug will be detected in urine. For most other drugs, metabolites will be detectable for a longer time than the main drug.
A drug test may look for only one drug, but most drug tests often test for multiple drugs with one sample. Although the drugs included in a drug panel test vary based on the reason for the test, the most common panel used to evaluate people for illegal drug use detects the presence or absence of five substances:
Other commonly tested substances include:
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Yes. Some kits can test urine samples in the privacy of your own home. Some kits may use breath, saliva or hair instead. The accuracy of these products is variable. They generally are less sensitive than the formal tests done in a laboratory. This means that a home test could be negative, but a laboratory test could be positive with the same sample.
The American Academy of Pediatrics cautions parents against drug testing their children at home. Research studies have shown that at-home testing doesn’t reduce drug use. At-home testing also comes with the potential for misinterpreting results, which may negatively affect the relationship between children and parents.
There’s nothing you need to do to prepare for a drug test.
Drug testing can be an emergency test, a scheduled test or it may be conducted randomly (for example, to meet ongoing employment requirements).
Depending on the circumstances, you may be asked to identify medications or supplements you’re taking.
Drug testing can be performed from small samples of your blood, hair, saliva, breath or, most commonly, your urine (pee).
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For a urine sample, you’ll pee into a clean container provided to you. In some instances, you may need to provide your urine sample in the presence of a nurse or technician to make sure that the sample did indeed come from you.
For a blood sample, a phlebotomist will draw a small amount of blood from a vein in your arm or hand.
After the provider has collected the sample, they’ll send it to a laboratory for analysis
For more HAV Rapid Testinformation, please contact us. We will provide professional answers.