An entire family presents with intense nocturnal pruritus and multiple papules, vesicles, and linear burrows between the fingers, wrists, and genitalia. Microscopy of material from a burrow shows a mite, eggs, and scybala. What is the first-line treatment?

• A Oral ivermectin 200 mcg/kg
• B Topical lindane 1% lotion
• C Topical benzyl benzoate 25% lotion
• D Topical permethrin 5% cream ✓

Explanation

Scabies is caused by the mite Sarcoptes scabiei var. hominis, and the first-line treatment recommended by most guidelines is topical permethrin 5% cream applied overnight from the neck downward for 8-12 hours, repeated after 1 week. All household and close contacts must be treated simultaneously. Permethrin is preferred over lindane due to its superior safety profile (lindane carries neurotoxicity risk in children and pregnant women). Oral ivermectin is an alternative for non-pregnant adults and for hyperkeratotic (Norwegian) scabies.

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.