Non-Systemic Medication for the Treatment of Prurigo Nodularis: A Systematic Review.

Prurigo nodularis (PN) is a skin disease characterized by firm, itchy, erythematous lesions. Treatment consists of systemic and non-systemic modes of therapy. Non-systemic forms of treatment are first-line and include topical corticosteroids, topical steroid-sparing agents, and phototherapy. The objective was to review the efficacy of non-systemic treatment used to treat PN. A systematic search was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and registered with PROSPERO (CRD42023412012). The search consisted of keywords and Medical Subject Heading (MeSH) terms and translated to Ovid MEDLINE, Embase, and Scopus. Google Scholar was also searched for the first 200 articles. Article quality of evidence was scored using GRADE criteria. The search yielded 1151 results; 37 met criteria for inclusion. There were 14 studies on phototherapy, and 11 studies on topical corticosteroids, most of which were also combined with topical antihistamines, antipruritics, and/or phototherapy. There were 2 studies each on topical antipruritics used in isolation, vitamin D analogues, and intralesional triamcinolone acetonide. There was 1 study each on topical pimecrolimus, tacrolimus, 2% dinitrochlorobenzene, cryotherapy, acupuncture, and the Paul Gerson Unna boot. Most were case reports and case series, although 2 randomized controlled trials on phototherapy and topical pimecrolimus were included. Corticosteroids had varying levels of positive response in patients and appeared more effective when used in combination or under occlusive dressing. Phototherapy is likely effective, but the risk of relapse is high. Cryotherapy may also be a lesion-directed agent to circumvent challenges to adherence and avoidance of systemic medication.

Systemic Medication for the Treatment of Prurigo Nodularis-A Systematic Review.

IMPORTANCE: Prurigo nodularis (PN) is a debilitating inflammatory skin disease characterized by red to violaceous pruritic lesions. The goal of therapy is to break the scratch-itch cycle. Treatment varies and often requires a multimodal approach to target both immune and neural mediated aspects of disease. OBJECTIVES: To review the efficacy of systemic treatment used to treat PN. EVIDENCE REVIEW: A systematic search of keywords and Medical Subject Headings was performed in Ovid MEDLINE, Embase, Scopus, and ClinicalTrials.gov. The first 200 results of an abbreviated search in Google Scholar were also included. PRISMA guidelines were followed and the review was registered on PROSPERO (CRD42023412012). GRADE criteria were used to assess articles for quality of evidence. FINDINGS: The search resulted in 1153 articles; 382 were duplicates, 643 were irrelevant, 19 were not retrieved, 21 were abstract only, and 88 are included in this review. There were 24 studies on dupilumab, 16 on thalidomide, 8 on cyclosporin, 7 on methotrexate, 3 each on lenalidomide and aprepitant, 2 each on alitretinoin, apremilast, baricitinib, gabapentin, intravenous (IV) immunoglobulins, pregabalin, tofacitinib, and 1 each on amitriptyline, azathioprine, butorphanol, isoquercitin, IV dexamethasone-cyclophosphamide/ oral cyclophosphamide, ketotifen, metronidazole, montelukast, nalbuphine, nemolizumab, serolopitant, tacrolimus, and herose derma zima capsule. CONCLUSIONS AND RELEVANCE: Dupilumab reduces pruritus and appearance of lesions and is associated with the fewest number of side effects. Thalidomide and pregabalin are also effective, but their long-term use is limited by muscle and nerve pain. Janus Kinase inhibitors may be beneficial, but large population studies are lacking.