ABSTRACT
Tumor lysis syndrome (TLS) is a metabolic disorder that is caused by acute lysis of massive tumor cells. We report a case with opioids-related severe respiratory depression induced by TLS. A 39-year-old man received chemotherapy for mycosis fungoides. Two hours after administration of chemotherapeutic agents, his renal function worsened, and he was diagnosed with TLS by laboratory and clinical findings. Moreover, he showed severe respiratory depression and pinpoint pupils, and become drowsy. These symptoms were attributed to oxycodone that had been administered to treat his tumor-related cutaneous pain, and were improved by injection of anti-opioids agent naloxone. In this case, we consider that the clearance of oxycodone was disrupted by renal dysfunction caused by TLS, leading to enhancement of the effects of oxycodone.