Sulfur 7% Cream Compared With Permethrin 5% Cream for Treating Scabies in Adults

Scabies is a highly pruritic skin infestation caused by Sarcoptes scabiei that remains endemic in many resource-limited settings. Permethrin 5% cream is recommended as first-line topical therapy in most international guidelines, but sulfur-based preparations remain widely used because of their low cost and long safety record, particularly in settings where permethrin is expensive or unavailable. Head-to-head comparative data between these two agents, especially data incorporating patient-centered outcomes such as sleep and treatment satisfaction, are limited.

This was a randomized, open-label trial conducted at Can Tho Dermatology Hospital, Can Tho City, Vietnam, enrolling 90 adults aged 18 years or older with a clinical diagnosis of ordinary (non-crusted) scabies, established using the 2020 International Alliance for the Control of Scabies (IACS) consensus criteria. Participants were randomly allocated in a 1:1 ratio to one of two treatment arms. In the sulfur arm, sulfur 7% cream was applied from the neck to the soles each evening, left on for 8-14 hours, and washed off, for three consecutive days. In the permethrin arm, permethrin 5% cream was applied in the same manner as a single overnight application, repeated once after seven days. Both groups received standardized instructions on decontamination of clothing, bedding and towels, and household contacts were offered the same regimen.

Participants were evaluated at baseline, week 2, and week 4. The primary outcome was complete cure, defined according to the 2017 European guideline as resolution of pruritus with no active or new lesions on examination. Secondary outcomes included pruritus severity (verbal rating scale), sleep quality and insomnia symptoms (Athens Insomnia Scale), treatment satisfaction (9-item Treatment Satisfaction Questionnaire for Medication), adverse events, and direct treatment cost. Associations between improvement in itching and improvement in sleep were also examined. Because outcome data were not normally distributed, between-group and within-group comparisons used non-parametric methods (Mann-Whitney U, Wilcoxon signed-rank, chi-square or Fisher's exact test, and Spearman rank correlation).

Inclusion criteria

• Adults aged 18 years or older
• Clinical diagnosis of ordinary (non-crusted) scabies, established using the 2020 International Alliance for the Control of Scabies (IACS) consensus criteria, category B:
• B1: burrow identified, or
• B2: typical lesions at male genitalia, or
• B3: typical lesions at typical sites plus pruritus and a history of close contact with a person with scabies or itch

Exclusion criteria

• Known allergy or intolerance to sulfur or permethrin
• Pregnant or breastfeeding women
• Hearing, visual, or cognitive impairment preventing reliable self-reporting of symptoms
• Self-discontinuation of study treatment before completion