A Case of Obstructive Jaundice-associated Pruritus Which Was not Improved by an Antihistamine and a Selective Serotonin Reuptake Inhibitor Treatment, but Was Responded to Nalfurafine Hydrochloride

<p>Introduction: We encountered a patient in whom pruritus was induced by obstructive jaundice associated with metastatic liver cancer. Nalfurafine hydrochloride, a selective κ receptor agonist, improved the patient’s pruritus. Case Presentation: The patient was a 70-year-old woman who developed metastatic liver tumor-associated jaundice after surgery for colorectal cancer. She developed pruritus, which was not improved by an antihistamine or a selective serotonin reuptake inhibitor treatment. Nalfurafine was administered for suspected central pruritus. The numerical rating scale for pruritus improved from 9 to 3. Discussion: Compared to other skin diseases such as urticaria and atopic dermatitis, pruritus that accompanies a systemic disease such as chronic renal failure and liver disease does not respond to existing therapeutic drugs in many patients. Chronic liver disease-associated pruritus is intractable and central. Pruritus through central and peripheral mechanisms was mixed in this patient; however, central pruritus may have been dominant. The antipruritic effect of nalfurafine has been confirmed. It may be an effective therapeutic drug for obstructive jaundice-associated pruritus.</p>

A case report with the coincidental complication of paroxysmal atrial fibrillation in the course of methadone administration due to cancer pain

Introduction: Paroxysmal atrial fibrillation (Paf) occurred in an inpatient who has been prescribed methadone for cancer pain in our palliative care unit, but oral administration of aprindine (antiarrhythmic agent) succeeded in defibrillation and methadone administration could be continued. Case: A 75-year-old man had developed multiple bone metastases after resection of thyroid cancer. Due to refractory cancer pain, switching from oxycodone to methadone was performed. Pain relief was achieved with methadone 40 mg/day and without QT interval prolongation. After methadone administration about 9 months, there suddenly became loss of appetite in the morning of one day. ECG examination revealed Paf onset. Aprindine 20 mg was orally administered for the purpose of defibrillation. After about 2 hours sinus rhythm was gained and later without recurrence. Conclusion: This case was considered to have the coincidental complication of paroxysmal atrial fibrillation in the course of methadone administration. If administration of antiarrhythmic agents is performed in a patient whom has been prescribed methadone, it is feared to lead to result in QT interval prolongation due to drug interactions. It is important to carefully select an agent that rarely leads to QT prolongation.