Do No Harm? Rethinking Urine Drug Screens in Treatment of Opioid Use Disorder

Drug Testing for Illicit Substances

Urine drug monitoring includes both UDS, a presumptive, often point-of-care test, and urine drug testing (UDT), a definitive laboratory test usually done with mass spectrometry. When a UDS returns with an unexpected result, the next step is often to send it for confirmatory UDT. False positives are common on urine drug screens.¹ Methamphetamines are particularly prone to false positives caused by cross-reactants, including many psychiatric and physical health medications commonly prescribed in primary care.²

According to the American Society of Addiction Medicine, drug testing should be done more frequently at the beginning of treatment or following a return to use, and less frequently as treatment progresses.³ These recommendations rely on expert opinion, as there is no evidence in the literature demonstrating that UDS improves patient oriented outcomes.⁴ Despite a substantial risk of harm to patients, guidelines recommend regular UDS as part of substance use disorder treatment. Lack of guidance on navigating the harms of UDS may be contributing to the ongoing use of routine UDS.

UDS to Evaluate Treatment

Drug screens can offer an opportunity for honest discussions with patients about their substance use. An unexpected positive result can open a dialog about a patient’s treatment plan. Some patients may appreciate drug screens as a way of staying accountable or as an external measure of their recovery.⁵ Clinicians require training to accurately interpret UDS. Clinicians should also consider that UDS lacks the nuance needed to fully capture substance use patterns. A strong patient-clinician relationship is more likely to yield rich information regarding substance use patterns and risk for overdose and infectious diseases.

UDS for Medication Adherence/Diversion

Although buprenorphine can be diverted, illicit buprenorphine is most often used to manage withdrawal symptoms rather than for euphoric effects.^6,7 However, if there are concerns a patient is diverting their medication, buprenorphine testing may be appropriate. Buprenorphine is often not part of a standard UDS panel and may require separate testing. This presents an opportunity to reduce reliance on broad panel UDS in favor of more targeted UDT. This may decrease the number of false positives and false negatives that result from using presumptive testing.

UDS to Monitor for Fentanyl Exposure

Clinicians may use also UDS as a tool for patients to understand their own exposure to fentanyl in the drug supply. In particular, this could be useful for patients who exclusively use stimulants or illicit benzodiazepines. The presence of fentanyl in urine could provide valuable information to patients who otherwise believe they are not at risk of overdose due to fentanyl and may lead to clinicians offering additional harm reduction tools such as naloxone. This approach should be used with the informed consent of patients. Clinicians can also recommend that patients test their own drugs using fentanyl test strips or local drug checking organizations. These strategies can provide people who use drugs with real-time data about the drug supply and can prompt patients to use safer use strategies.⁴

Harms

A key challenge in navigating UDS in patient care is the absence of high-quality evidence around substance monitoring, including the harms that accompany urine drug monitoring. The experience of “peeing into a cup,” especially in settings that are heavily monitored to prevent tampering with the sample, can feel invasive and degrading.⁵ Particularly for people with a history of trauma, supervised or heavily monitored sampling is intrusive and can compound patient trauma. UDS can further stigmatize an already stigmatized group of patients.⁵ Drug screening may cause patients to believe that their clinician does not trust them or is expecting them to return to use. We propose that these interpersonal harms could lead to additional harms if a patient feels reluctant to share challenges with recovery, feels they cannot disclose a return to use of substances, or chooses to disengage from treatment.

A positive result for illicit substances on UDS can also lead directly to patient harms. Pregnant and birthing people are particularly vulnerable; a positive screen for illicit substances or medications for opioid use disorder (MOUD) – including a false positive – can result in contact with Child Protective Services (CPS).^8,9 Racial bias in drug screening differentially exposes people to the risks of criminal-legal involvement, with Black pregnant patients in particular more likely to be screened for substances than their White counterparts.^10,11 Qualitative and quantitative research has shown the trauma and subsequent health problems caused by family separation.^12,13 The historic and present uses of drug screening to police Black parents and parents with substance use disorder (SUD) must be considered when ordering UDS.¹⁴