By this point in the course, you should be comfortable recommending various treatment options, but how do you know if a treatment is working or not? How can you monitor progress? In this lesson, you will learn how drug toxicology can be used to monitor substance use disorders. More importantly, you will learn how to use drug testing to start a dialogue with your patients and get a sense of how they have been doing since you last saw them. Simply speaking, drug tests are designed to measure whether a particular substance has been used with a particular window of time. While there's limited evidence on whether the use of drug testing actually can lead to improve clinical outcomes in addiction treatment, it can be used as a tool for supporting your patient's recovery. The actual test is just the first part of the equation. We will review some of the biological matrices used in drug testing now. Here's a quick quiz. Which of the following specimens can be used for drug testing? Urine, saliva, blood, sweat or hair. Drugs can be identified in all the previously mentioned matrices and they are useful for different scenarios and have different advantages. Today, urine remains the most commonly used of all drug-testing matrices. It is the least expensive to analyze, it has well-established cut-off levels, and use guidelines. Some drawbacks to using urine drug testing is that it's most prone to tampering through dilution or substitution. Here, it is important to mention that the creativity of individuals seeking to subvert this type of testing is astonishing. There exists an entire industry dedicated to making and marketing products intended to assist patients in interfering with urine drug screening. While the need for observed specimen collection can negatively affect the patient's trust, it is important when using this testing matrix to ensure the integrity of the specimen. In the past decade, the use of oral fluid or saliva testing has become more common. For this analysis, the specimen collection is done with oral swabs and can be collected by the patient, nurse or provider, making it less susceptible to tampering than urine. Understandably, most patients prefer this route of screening to observed urine collection. Another positive aspect is that it is highly sensitive and specific for methadone and opioids of abuse. The downside is that this type of testing does require a specimen analysis to be done by a qualified offsite laboratory. Blood analysis is another matrix used in screening for substance use, but is primarily done in the emergency department setting where there is a need to assess intoxication or impairment. To finish up the rest of the matrices, there's not sufficient evidence to support the use of hair or sweat testing in addiction treatment. Although, if necessary, hair testing can be utilized to detect long term patterns of use. Regardless of the matrix being used, the initial screening test performed is an immunoassay which results can be returned quite quickly. The results of the confirmatory testing are almost never available in a sufficiently, timely manner to play a role in the clinical management of acute medical problems or counseling situations. When confirmatory testing is needed, the most common test is gas chromatography/mass spectrometry. It is likely that your medical setting will have certain parameters and policies about what testing options are available and recommended. Typically, urine tests are used because of their timeliness and affordability. One thing you'll want to keep in mind is what drugs of abuse you can test for to know if it includes your patient's primary substance. Some of the most commonly screened drug classes and their detection windows are: amphetamines, which can be detected within 1-3 days, benzodiazepines, which can be detected in 1-7 days, but this varies by the half-life of the medication; cannabinoids, 5-7 days, this is with moderate use; cocaine, 1-3 days; methadone, 3-7 days; opioids, 1-3 days; phencyclidine or PCP, 1-7 days. Other basic drugs of abuse screens can be included, but vary by medical or lab facility. As we discuss random testing, it is important to remember that drug screening results can often positively or negatively affect many situation, therefore accuracy is of highest importance. So a real worry for anyone undergoing drug testing, whether it be by urine, saliva or blood, is the possibility of a false-positive result. The increased use of on-site random drug testing and home testing kits emphasize the need for reliable confirmatory testing. The negative consequences of false-positive drug testing can include removal from treatment for addiction, jail time, loss of privileges in a probation setting or loss of employment. In rare cases, a drug test may report the presence of illegal or prescription drugs in the immunoassay although person has not used these drugs. While this is not common, no test is 100 percent accurate. It is important that you get a complete and accurate history of all prescriptions, over-the-counter and vitamin dietary supplement or herbal drugs your patient is taking prior to the time of sample collection. Many assays, particularly immunoassays, can yield false-positive results if specific, cross-reacting medications or drugs are present in the sample collected. Some of the cross-reacting substances include the following: false-positive amphetamine results can be from pseudoephedrine, ephedrine, phenylephrine, and other commonly used medications such as beta blockers. False-positive opioid results can be from poppy seed ingestion and bagels or pastries or the antibiotic class known as quinolones. False-positive PCP results can be from over-the-counter cold medications such as dextromethorphan or the antidepressant venlafaxine. False-positive cannabinoid or marijuana results can be from hemp-containing food products or the anti-inflammatories ibuprofen or naproxen. In treatment, the toxicology test itself is part 1 and the patient's voice is part 2. What I mean by that is, drug testing should never be the sole determinant in an assessment of a substance use disorder. Drug testing should always be done in combination with a patient's self-reported statement on their substance use. Keep in mind that self-reporting may be unreliable if a patient faces high-stakes negative consequences if a substance of abuse is detected. Here, discrepancy between the self-report and drug test results can be used as a point of engagement for the provider. In these scenarios, the results can be used as a way to explore denial, motivation, triggers, and actual substance use patterns with patients. Drug testing should not be punitive, rather, it should be therapeutic. In other words, you're not trying to catch your patients. Instead, you're trying to understand your patients. Either via a paper form or an in-person interview, you should gather more information from your patients. For example, let's look at this sample medical management visit form. The most important question to ask is if there has been any drug use since the last visit? If yes, dig deeper and ask, how much and under what circumstances? You can also note signs or symptoms like mood or physical appearance that might indicate a return to use. You can also ask if there's been any problems with the following: drug or alcohol use, psychiatric or medical health, employment, social/family or legal issues. If any problems come up, take some time to address them with your patient and update the treatment plan accordingly. These questions are part of treatment. You don't want to interrogate or intimidate your patients. Before starting any follow-up visit, you might want to take some time to set expectations and reiterate that you will review a standard set of questions that you ask everyone in your care. To review, drug testing should be a routine part of initial and ongoing patient assessment of recent substance abuse in all addiction treatment or primary care settings. Drug test results should not be used as the sole determinant when making patient care decisions, but used in conjunction with patient self-reports, treatment history, and a complete history and physical examination. Test matrix selection for monitoring should also be individualized based on the patient's drug of choice, prescribed medications, and clinic setting.
