Doctors Lag Behind Law Enforcement in Identifying Emerging Drug Threats

The illicit drug supply is rapidly evolving, with new synthetic substances like nitazenes, medetomidine, and cychlorphine appearing in quick succession. While rapid tests for these emerging drugs are available and can produce results within minutes for law enforcement, employers, and the public in states where they are decriminalized, physicians in emergency rooms treating overdoses cannot readily use them.

This disparity arises primarily from regulatory distinctions. Many available tests are designated for forensic use only. To be used in clinical settings for living patients, tests must receive approval from the Food and Drug Administration (FDA) as diagnostic tools. Additionally, point-of-care tests used at the bedside must also meet the criteria for waived status under the Clinical Laboratory Improvement Amendments (CLIA), a process ensuring they are simple and low-risk enough for clinical use. While these requirements ensure accuracy and reliability for medical decisions, they create a significant delay in providing clinicians with immediate information.

This testing gap was evident with fentanyl. Even as rapid tests for the opioid became available outside clinical settings in early 2023, hospitals often relied on slower spectrometry testing that could take an hour or longer. By the time FDA-cleared and CLIA-waived rapid fentanyl tests became available, the illicit market had already shifted.

The situation has been further complicated by the emergence of other dangerous substances. Starting around 2020, xylazine, an animal tranquilizer, began appearing in the fentanyl supply. While naloxone can reverse the opioid effects, it does not counteract xylazine, leaving patients dangerously sedated or unstable. Xylazine is also associated with severe skin wounds and complex withdrawal syndromes. Subsequently, medetomidine replaced xylazine in some supplies. Like xylazine, it is not reversed by naloxone and can cause profound sedation and cardiovascular instability. Its withdrawal can lead to severe hypertension and tachycardia, potentially linked to heart attacks.

There are currently no point-of-care tests for medetomidine or other emerging substances like cychlorphine, an opioid not detected by fentanyl tests. Consequently, clinicians often rely on delayed information from law enforcement seizures, public health alerts, and outdated fatality data, rather than real-time testing at the bedside.

To address this gap, experts suggest the FDA establish an expedited pathway for clinical tests targeting emerging drug threats. This pathway could be triggered by designations from agencies like the CDC or the Office of National Drug Control Policy when a substance poses a significant and growing public health concern. The FDA's existing dual pathway for clearance and CLIA waivers could be adapted and prioritized for these urgent threats, bypassing the standard lengthy review process.

Federal and state agencies could also provide funding for independent validation of these tests, particularly for substances with small but significant markets. This financial support could bridge the gap for manufacturers who might otherwise find it economically unfeasible to conduct extensive clinical studies for rapidly changing drug supplies.

It is important to note that point-of-care testing is intended as a presumptive tool, to be confirmed with further testing if necessary. Clinicians routinely make decisions by synthesizing multiple sources of information, including patient history, physical exams, vital signs, and laboratory results. Rapid drug screening would serve as an additional valuable tool in this process, helping to clarify the unknowns presented by the evolving drug supply.

Implementing such testing in emergency departments could also create an early-warning system, allowing for quicker responses to emerging crises. Front-line healthcare providers, who are critical in managing the overdose crisis, should have access to the most advanced testing tools to aid in timely and effective patient care.