This is a prospective, single-arm, open-label, pilot clinical study to evaluate the efficacy and safety of topical 10% high-concentration 35 kDa hyaluronan (HA35) gel for ultra-rapid relief of moderate-to-severe skin pruritus from diverse etiologies (eczema, neurodermatitis, insect bites, urticaria, postoperative wound itch). Eligible participants will receive a single topical application of HA35 gel. The primary objective is to assess pruritus relief at 10 seconds, 45 minutes, 8 hours, 12 hours, and 24 hours post-application. Safety and local skin tolerability will be evaluated throughout the observation period. This is a minimal-risk, non-pharmacological, non-invasive intervention.

This prospective, single-center, single-arm, open-label pilot clinical study investigates the ultra-rapid antipruritic efficacy and safety of topical 10% high-concentration 35 kDa hyaluronan (HA35) gel for managing moderate-to-severe skin pruritus caused by various conditions including eczema, neurodermatitis, insect bites, urticaria, and postoperative wound pruritus.

Eligible subjects will receive a single topical application of HA35 gel evenly spread over the pruritic skin area. Pruritus intensity will be assessed using a 0-10 Numeric Rating Scale (NRS) at baseline, 10 seconds, 45 minutes, 8 hours, 12 hours, and 24 hours after application. Changes in associated erythema, swelling, and wheals will also be observed.

Local skin irritation, allergic reactions, and adverse events will be monitored continuously for safety assessment.

This is a non-invasive, non-pharmacological topical intervention with minimal risk to participants. All procedures will be conducted in accordance with the Declaration of Helsinki, and written informed consent will be obtained from all subjects prior to enrollment.

Inclusion Criteria:

• Age 18-65 years, male or female
• Moderate-to-severe skin pruritus (NRS ≥6) due to eczema, neurodermatitis, insect bites, urticaria, or postoperative wound itch
• Able to understand and complete NRS assessments independently
• Signed written informed consent

Exclusion Criteria:

• Topical corticosteroid/antihistamine use within 2 weeks
• Infected, broken, or exudative skin lesions at the application site
• Known hypersensitivity to hyaluronan or gel components
• Severe systemic disease or immune dysfunction
• Pregnant or lactating women