Background: Zinc is a micronutrient essential for taste perception and may be prescribed for dysgeusia in cancer patients undergoing treatment. However, overconsumption of zinc can lead to copper deficiency, which is likely under-recognized and can present as fatigue, nausea, anemia, and myelopathy. Case presentation: A patient in his 70s with multiple myeloma and gastroparesis taking zinc supplementation to treat dysgeusia for the past 2 years presented with generalized fatigue, lightheadedness, nausea, neutropenia, anemia, gait disturbance, and worsening numbness and tingling in the bilateral lower extremities and hands. He was found to have hypocupremia in the setting of prolonged zinc supplementation and admitted for inpatient treatment with IV cupric chloride. His symptoms gradually improved over the course of approximately 5–6 weeks. Conclusions: Clinicians should be vigilant about screening for copper deficiency symptoms in patients taking zinc supplementation and avoid prolonged courses or overprescribing of zinc. Hypocupremia should be promptly diagnosed and treated to prevent permanent neurological deficits.

Importance: Urine drug test (UDT) can help screen and monitor aberrant controlled substance use among patients requiring opioid therapy for cancer pain. However, data on UDT utilization in patients with cancer pain remains limited. Objective: To determine the rate of UDT ordering and the factors associated with UDT order placement and the frequency and type of abnormal UDT findings. Methods: This retrospective study included adults (≥18 yrs) with a cancer diagnosis receiving prescription opioids for pain in an ambulatory pain clinic from November 2017 through April 2018. Descriptive statistics summarized patient characteristics and UDT findings. Logistic regression was used to identify factors associated with UDT ordering. Results: Five hundred fifty-eight patients were included in the study; the median age was 61 years, 52% were female, 74% were White, and 93% had active cancer. One hundred forty-one patients (25%) had UDT orders. On multivariate analysis, UDT ordering was associated with SOAPP-14 score ≥ 7 (OR, 2.03 95% CI 1.19–3.47 p = 0.009) and a history of substance use disorder (OR, 2.87 95% CI: 1.39–5.75 p = 0.004). Among those tested, 49 (35%) had abnormal results. A total of 80 abnormalities were identified, with some UDTs showing multiple findings; the most common was the absence of prescribed opioids (48%). Conclusions: Only one in four patients receiving opioids in an ambulatory cancer pain clinic received a UDT order, suggesting a more selective rather than routine use. UDT ordering was more common among patients with a SOAPP-14 score ≥ 7 and a history of substance use disorder. Among patients who underwent UDT, approximately one-third had abnormal results, with the absence of prescribed opioids or their expected metabolites being the most common finding. These findings suggest that UDT may provide important clinically relevant information as a component of comprehensive opioid monitoring. Further research is needed to establish evidence-based approaches to UDT implementation that promote consistent opioid safety practices.