尿液毒品检测（UDT）在监测长期使用阿片类药物治疗（COT）的患者中，对非医疗阿片类药物使用（NMOU）起着重要作用。但是，UDT有时会不一致且具有误导性。本文报告了一个患者使用丁丙诺啡贴片并出现假阴性结果的案例。一名70多岁患有转移性乳腺癌的女性因T6椎体压迫性骨折引起的疼痛无法控制，口服舒痛林每6小时50毫克未能缓解。由于对氢吗啡过敏，我们的团队给予了一片5微克/小时的丁丙诺啡贴片。随后，她表达了出色的疼痛控制，并且临床医生在检查时确认了贴片的位置。在就诊期间进行了UDT。UDT结果同时对丁丙诺啡及其代谢物呈阴性。文献回顾显示低剂量丁丙诺啡贴片患者的假阴性UDT结果相对较常见。通过全面的体格检查、处方药物监控程序回顾以及筛查工具得出的安全评分，其NMOU风险较低。丁丙诺啡对呼吸抑制存在剂量上限效应，并且成瘾风险较低。然而，当低剂量使用该药物时，尿液中可能没有足够的代谢物，导致假阴性UDT结果。这样的结果可能影响患者与医生之间的关系。除UDT外，详尽的病史、NMOU筛查、体格检查、PDMP回顾以及对阿片类药物代谢的深入了解，都对指导疼痛管理起到必要的作用。

Urine drug testing (UDT) plays a significant role in monitoring patients on chronic opioid therapy (COT) for non-medical opioid use (NMOU). UDT, at times, can be inconsistent and misleading. We present a case where a patient on a buprenorphine patch had false negative results.A female in her 70s with metastatic breast cancer presented with uncontrolled pain from a T6 compression fracture. She had no relief with tramadol 50 mg every 6 hours as needed. Due to an allergic reaction to hydromorphone, our team prescribed a buprenorphine patch of 5 μg/h. Subsequently, she expressed excellent pain control, and the clinician confirmed the patch placement on examination. She underwent a UDT during the visit. The UDT was negative for both buprenorphine and its metabolites. The literature review showed that false negative UDT results are relatively common among patients with low-dose buprenorphine patches. The combination of a thorough physical examination, a review of the Prescription Drug Monitoring Program, and reassuring scores on screening tools placed her at low risk for NMOU.Buprenorphine has a ceiling effect on respiratory depression and a lower risk for addiction. However, when used in low doses, the drug might not have enough metabolites in the urine, leading to a false negative UDT. Such results might affect patient-physician relationships.In addition to the UDT, a thorough history, screening for NMOU, physical exam, a review of PDMP, and a good understanding of opioid metabolism are necessary to help guide pain management.