Modulation of mu-opioid pathway for the treatment of pruritus: a systematic review of 1,146 patients

Clinical Snapshot

Key Findings

• P Value: Not reported

• Effect Size: Not quantified due to narrative synthesis

• Primary Outcome: Clinically meaningful reductions in pruritus intensity using validated itch scales

• Nnt Or Sensitivity: Not calculated due to heterogeneity

• Confidence Interval: Not reported

Clinical Application

Limited by off-label use requirements and need for specialist supervision, particularly for systemic opioid modulators Relevant to Australian dermatology and nephrology practice; naltrexone available on PBS for alcohol dependence but off-label use for pruritus requires private prescription and specialist consultation Patients with refractory pruritus of dermatologic or systemic origin where conventional therapies provide incomplete relief

Abstract

BACKGROUND: Pruritus is a debilitating symptom and conventional therapies often provide incomplete relief. The μ-opioid receptor (MOR) pathway is a key regulator of itch, and μ-pathway-modulating agents are increasingly used off-label for refractory pruritus. AIM: This systematic review evaluates the efficacy, safety, and real-world use of μ-opioid pathway modulators for pruritus of dermatologic and systemic origin. METHODS: Following PRISMA guidelines (PROSPERO CRD420251207101), a comprehensive search of four databases identified 3,274 records, of which 69 studies met inclusion criteria, comprising 14 randomized controlled trials (RCTs; n = 795) and 55 non-randomized studies (n = 351). Owing to substantial clinical and methodological heterogeneity, findings were narratively synthesized. RESULTS: Five RCTs evaluated dermatologic conditions, including atopic dermatitis, prurigo nodularis, chronic urticaria, and lichen planopilaris, while nine RCTs assessed systemic pruritus, predominantly cholestatic and uremic pruritus. RCTs investigated oral or topical naltrexone, intravenous naloxone, nalmefene, and extended-release nalbuphine, with most demonstrating clinically meaningful reductions in pruritus intensity using validated itch scales. Non-randomized studies reported improvement across a wide range of dermatologic and systemic conditions, with adverse events generally mild and well tolerated. CONCLUSIONS: Overall, μ-opioid pathway modulators show promising efficacy with acceptable short-term safety across diverse pruritic conditions, although larger high-quality RCTs are required to define optimal dosing and support clinical translation.

References

1. 1.Ahmed, K. M. A., Abu Suleiman, A., Alnajdawi, A. I., Abdulkader, D., Ahmed, A. M., Moustafa, A. R. A., & Horton, E. (2026). Modulation of mu-opioid pathway for the treatment of pruritus: a systematic review of 1,146 patients. The Journal of Dermatological Treatment. https://doi.org/10.1080/09546634.2026.2646801