What treatment is used against the scabies mite? - briefly
The first‑line therapy is a single application of 5 % permethrin cream, left on the skin for 8–14 hours and repeated after one week; for those unable to use topical agents or with extensive infestation, oral ivermectin (200 µg/kg) administered on two separate days provides an effective alternative.
What treatment is used against the scabies mite? - in detail
Scabies infestation is eradicated primarily with topical acaricides and, when appropriate, systemic agents. The first‑line topical preparation is a 5 % permethrin cream applied to the entire body from the neck down (including genitalia) and left for 8–14 hours before washing off. A single application is usually sufficient; a second dose applied one week later eliminates surviving mites and prevents reinfestation.
Oral ivermectin, 200 µg/kg, is the preferred systemic option for patients unable to use topical therapy, for extensive disease, or for crusted scabies. The regimen consists of two doses spaced 7 days apart; severe cases may require a third dose on day 14. Ivermectin is contraindicated in pregnancy and in children weighing less than 15 kg.
Second‑line topicals include:
- 10 % sulfur ointment, applied nightly for 3–5 days; safe in infants and pregnant women but odorous and messy.
- 25 % benzyl benzoate lotion, applied to dry skin, left for 24 hours, then washed; repeated after 24 hours.
- 10 % crotamiton cream, applied for 24 hours and repeated after 24 hours; less effective than permethrin.
- 0.5 % lindane shampoo, applied for 8 hours; restricted due to neurotoxicity risk, used only when alternatives fail.
Adjunct measures:
- Treat all household members and close contacts simultaneously, regardless of symptoms, using the same regimen.
- Launder bedding, clothing, and towels in hot water (≥50 °C) and dry on high heat; items that cannot be washed should be sealed in plastic for at least 72 hours.
- For crusted scabies, combine oral ivermectin with daily topical therapy and consider keratolytic agents (e.g., salicylic acid) to improve drug penetration.
Monitoring includes reassessment 2–4 weeks after treatment; persistent itching may reflect post‑scabetic inflammation rather than ongoing infestation. In cases of treatment failure, confirm compliance, consider resistance, and switch to an alternative agent or combination therapy.