A nursing home outbreak of scabies affects 35 residents and 12 staff. Three residents have hyperkeratotic plaques on palms and soles with thousands of mites — crusted (Norwegian) scabies. First-line treatment for the index cases (crusted scabies) and their close contacts is:

• A Topical permethrin 5% cream weekly for 4 weeks for crusted cases; single dose for contacts
• B Topical benzyl benzoate 25% alone for all cases
• C Oral ivermectin (200 µg/kg/dose on days 1, 2, 8, 9, 15, and 22) combined with topical keratolytics and 5% permethrin cream for crusted scabies ✓
• D Topical lindane 1% cream as first-line for outbreak control

Explanation

Crusted (Norwegian) scabies requires intensive combination treatment due to the high mite burden: oral ivermectin in multiple doses (Days 1, 2, 8, 9, 15, 22 — or at minimum Days 1 and 8) combined with topical scabicidal agents (5% permethrin applied from neck down daily or alternate days for 1–2 weeks) and keratolytics (salicylic acid ointment) to enable penetration. Single-course topical permethrin is inadequate for crusted scabies. Contacts receive standard treatment (single dose oral ivermectin + permethrin). Lindane is no longer recommended due to neurotoxicity. Strict infection control isolation is required.

Reference: Neena Khanna Illustrated Synopsis of Dermatology & STD, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.