Evaluation of the Use of Naltrexone for Cholestatic Pruritus

Abstract

OBJECTIVE Pruritus is a common symptom of liver disease, managed with various medications including opioid antagonists like naltrexone. Current literature surrounding the safety and efficacy of naltrexone for cholestatic pruritus is limited. Our objective was to describe naltrexone prescribing practices for cholestatic pruritus. METHODS We conducted a single-center, retrospective review of inpatients who received naltrexone for cholestatic pruritus. We gathered information on naltrexone dosing, frequency, dose adjustments, duration, elevations in liver function tests (LFTs), and use of additional antipruritic agents. RESULTS Thirty-nine patients and 122 dosing regimens were included for analysis. Most patients were male (56.4%) with a median age of 6.32 years (range, 0.63–18.89). The median weight-based doses of naltrexone were 1.45 mg/kg/dose (IQR, 0.84–2.81) and 1.86 mg/kg/day (IQR, 0.97–3.37). The median flat doses were 25 mg/dose (IQR, 12.25–50) and 50 mg/day (IQR, 25–50). The median number of additional antipruritic agents used before and after naltrexone initiation was 3 (IQR, 2–4) and 4 (IQR, 3–5), respectively (p < 0.001). The most common elevated LFTs were total bilirubin and alanine aminotransferase (ALT), occurring in 15% of patients. CONCLUSIONS Naltrexone dosing ranged between 1 and 2 mg/kg/dose once or twice daily, with larger weight-based doses prescribed in younger and lower-weight patients. Naltrexone was commonly added as a fourth-line agent and did not lead to discontinuation of other antipruritic therapies. Larger, prospective, controlled studies are needed to assess the safety and efficacy of naltrexone for cholestatic pruritus.