How should simple prurigo be treated?

Simple prurigo, also known as prurigo simplex or idiopathic prurigo, is a chronic, intensely itchy dermatosis characterized by discrete, firm, excoriated papules—often on extensor surfaces such as the dorsal hands, forearms, shins, and buttocks. It predominantly affects adults and is thought to arise from a combination of neurogenic inflammation, peripheral nerve sensitization, and habitual scratching, rather than an underlying systemic disease or allergic trigger.

Management focuses on breaking the itch-scratch cycle and reducing neuroinflammatory activity. First-line therapy includes high-potency topical corticosteroids (e.g., clobetasol propionate 0.05% ointment) applied once or twice daily under occlusion for limited areas, combined with emollients containing soothing agents like colloidal oatmeal or menthol. Oral antihistamines—particularly second-generation agents such as loratadine, fexofenadine, or cetirizine—are used primarily for sedation and nighttime symptom control, though their efficacy in true prurigo is often modest due to non-histaminergic itch pathways.

For refractory cases, systemic interventions may be warranted. Narrowband UVB phototherapy (2–3 sessions per week) demonstrates consistent benefit by modulating cutaneous immune responses and decreasing sensory nerve fiber density. Low-dose oral corticosteroids (e.g., prednisone 10–20 mg/day for 2–4 weeks) can provide rapid relief during acute flares but are not suitable for long-term use. Emerging evidence supports off-label use of neuromodulators—including gabapentin (300–900 mg/day) or pregabalin (75–150 mg/day)—to target central and peripheral sensitization. In select patients unresponsive to conventional therapy, dupilumab—a monoclonal antibody targeting IL-4Rα—has shown promising results in case reports and small series, reflecting the role of type 2 inflammation in some prurigo phenotypes.

Non-pharmacologic strategies are integral: behavioral counseling to address scratching habits, use of cool compresses, wearing soft cotton gloves at night, and identifying and minimizing potential exacerbating factors (e.g., stress, dry environments, wool clothing). A thorough evaluation—including complete blood count, liver and renal function tests, thyroid studies, and screening for underlying atopy or autoimmune conditions—is recommended to exclude secondary causes before confirming a diagnosis of simple prurigo.